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What you have here is a copy of THE IBM XT CLONE BUYER'S GUIDE. This
book has been released into the public domain as a "sharebook". You are
free and encouraged to make copies and distribute them in electronic
form without alterations to other bulletin boards, friends, etc. The
book may not be printed or used in any other publication without
permission. If you feel the book has been of value send $5 to the
address below. The entire book is presented here without charts,
photographs, drawings, illustrations, and tables. If you would like the
latest complete updated copy send $9.95, plus $2 shipping (Ca. residence
add $.65 sales tax) to Modular Information System, 431 Ashbury St., San
Francisco, California, 94117.

Keep your eye out for the IBM AT CLONE BUYER'S GUIDE AND HANDBOOK which
will be available in the fall of 1987. The price will be $19.95. Also
available in early 1988 will be the 386 COMPUTER BUYER'S GUIDE AND
HANDBOOK at $24.95.

The following reviews, press release, and book review may be used in any
publication without permission.


What they're saying about THE IBM XT CLONE BUYER'S GUIDE:

"....outlines everything you need to know about piecing together your
own clone or what to look for when buying an assembled clone." John

"....useful resource for those thinking about buying a PC clone."

"I highly recommend it to anyone contemplating getting a computer...."
Jerry Pournelle, BYTE MAGIZINE

".... contains good, hard information presented in a breezy, easy-to-

"....good starting point for your research in the best system for your

"....Edwin Rutsch has performed a valuable service to the microcomputer

"You should get this book before you buy any computer." Art Kliener,

"Your book contains such useful information that I'm making it required
reading for all my staff." COMPUTER SPECIALTY BOOK STORE OWNER, San
Jose, CA.

"Thank you for writing such a concise and easily understandable book on

PC Clones. Thanks to you I was able to go to several stores, speak with
some authority on the merits of the computers I was shown, discover that
some stores (Radio Shack in particular) had salespeople who knew even
less than I, and in the end, make what I felt was a good choice." Kay

"Consumers ordinarily don't know what they're getting when they buy
clones. The IBM XT CLONE BUYER'S GUIDE is a big help to potential
computer buyers trying to buy or piece together clone computers." The
Oakland Tribune.

Rutsch's book, which can be ordered for $11.95 postpaid from Modular
Information Systems, 431 Ashbury St. SF, CA. 94117, is a +good
investment if your thinking about buying or assembling an XT." Lonnie
Hudkins, Buffalo News.

"Before you buy, get the frequently updated IBM XT CLONE BUYER'S GUIDE -
filled with detailed advice and user-group lore." THE ESSENTIAL WHOLE

Information System, 431 Ashbury St. SF, CA. 94117 (11.95 postpaid)


Edwin Rutsch's THE IBM XT CLONE BUYER'S GUIDE (Modular Information
Systems, 431 Ashbury St., SF, CA 94117, $9.95 plus $2 shipping) presents
a clear understanding of the newest revolution in the microcomputer
industry, the victory of the 'generic' clones over the established
industry giant, IBM. In addition, the book gives a thorough
understanding of the microcomputer industry as a whole, describing all
the issues that confront those of us considering the purchase of a non-
IBM computer. The GUIDE gives complete, concise, infinitely
comprehensible "reader friendly" advice. Clones offer IBM quality
(or better) at a fraction of IBM's price. They should not be confused
with computers that are merely compatible with the IBM. The clones are
made almost entirely of parts that are exact duplicates of those
utilized by IBM; they are virtual copies. Their hardware is totally
interchangeable with the IBM XT. Rutsch's delightfully illustrated
book provides all the answers for the prospective computer buyer. In
fact, he'll probably answer a lot of good questions you haven't even
thought of yet. He's been doing just that as founder of the nation's
first XT clone user's group. More than worth its weight in computer
chips, this book should become required reading for anyone who demands
the highest quality at the lowest possible cost.


Edwin Rutsch
1986; Modular Information Systems, 431 Ashbury St.,
San Francisco, CA 94117.: $9.95 plus $2 shipping; 127 pp.;
37 illustrations; 19 photographs; 2 tables,
ISBN 0-939325-12-8

With the publication of Edwin Rutsch's book, THE IBM XT CLONE BUYER'S
GUIDE, available by mail order, the word clone takes on a whole new
meaning, one that is certain to have an immediate and significant
effect. Whether you are extremely nervous about even considering the
purchase of a computer, or about to build your 27th telecommunications
network, you should read this book.

Rutsch is on to something. That "something" being IBM clones, computers
that are just as good if not better than the name brand and incredibly
less expensive. Available since mid-1985, they are built with the same
sized parts as the IBM computers, thus assuring that repair, maintenance
and expansion will be available as long as IBM is the industry standard.
(Not much to worry about on that account.)

As Rutsch clearly explains, clones should not be confused with computers
that are promoted as being compatible to IBM. Compa- tibles will
probably run most of the software developed for IBM, but all of the
parts may not be interchangeable. The best of them can therefore become
extinct by whim or financial setback of even a major manufacturer.

The clones, however, are exact duplicates of the IBM except for one part
called a Basic Input Output System (BIOS). This is the only part of
both the PC and XT that IBM has a copyright on. Everything else can be
bought right off the shelf. In fact, Rutsch offers surprisingly clear,
concise step-by-step illustrated instructions for making your own clone.

Whether you're "just looking," or you can carbon date your experience
with computers, THE IBM XT CLONE BUYER'S GUIDE is a sane, short,
delightfully illustrated, "reader-friendly" book. It will answer all
your questions as well as some you haven't yet considered. As founder
of the nation's first XT clone users group and head of a San Francisco
microcomputer consulting firm, Rutsch has amassed considerable

After reading his book, two things become very obvious: the clones are
coming, and sooner or later, you're going to want one. Besides, if you
don't like the terminology, you can always dump the word "clone" and opt
for "generic." As cost-conscious consumers, we've all learned how
important that word can be.


Version 2.0



Published by
Modular Information Systems
431 Ashbury Street
San Francisco, CA 94117

Information System, 431 Ashbury St. SF, CA. 94117 (11.95 postpaid)



IBM COMPATIBLES. . . . . . . . . . . . . . . . . . . .
A T & T 6300 . . . . . . . . . . . . . . . . . . . . .
Compaq Deskpro . . . . . . . . . . . . . . . . . . . .
Epson Equity . . . . . . . . . . . . . . . . . . . . .
IBM. . . . . . . . . . . . . . . . . . . . . . . . . .
IBM PC Jr. . . . . . . . . . . . . . . . . . . . . . .
IBM PC . . . . . . . . . . . . . . . . . . . . . . . .
IBM XT . . . . . . . . . . . . . . . . . . . . . . . .
IBM AT . . . . . . . . . . . . . . . . . . . . . . . .
Kaypro PC. . . . . . . . . . . . . . . . . . . . . . .
Leading Edge Model M . . . . . . . . . . . . . . . . .
Leading Edge Model D . . . . . . . . . . . . . . . . .
Tandy 1000 . . . . . . . . . . . . . . . . . . . . . .
Tandy 1200 . . . . . . . . . . . . . . . . . . . . . .

NON-IBM COMPATIBLES. . . . . . . . . . . . . . . . . . . .
Apple IIe. . . . . . . . . . . . . . . . . . . . . . .
Apple IIc. . . . . . . . . . . . . . . . . . . . . . .
Apple MacIntosh. . . . . . . . . . . . . . . . . . . .
Commodore 128. . . . . . . . . . . . . . . . . . . . .
Commodore Amiga. . . . . . . . . . . . . . . . . . . .
CP/M . . . . . . . . . . . . . . . . . . . . . . . . .

BUYING THE XT CLONE . . . . . . . . . . . . . . . . . . . .
RETAILERS. . . . . . . . . . . . . . . . . . . . . . .
"CLONE DEALERS". . . . . . . . . . . . . . . . . . . .
"GARAGE DEALERS" . . . . . . . . . . . . . . . . . . .
COMPUTER SWAPS . . . . . . . . . . . . . . . . . . . .
MAIL ORDER . . . . . . . . . . . . . . . . . . . . . .

CHOOSING THE RIGHT PARTS. . . . . . . . . . . . . . . . . .
MOTHER BOARDS. . . . . . . . . . . . . . . . . . . . .
CASES. . . . . . . . . . . . . . . . . . . . . . . . .
POWER SUPPLIES . . . . . . . . . . . . . . . . . . . .
FLOPPY DISK DRIVES . . . . . . . . . . . . . . . . . .
FLOPPY DISK CONTROLLERS. . . . . . . . . . . . . . . .
DISPLAY CARDS. . . . . . . . . . . . . . . . . . . . .
MONITORS . . . . . . . . . . . . . . . . . . . . . . .
KEYBOARDS. . . . . . . . . . . . . . . . . . . . . . .

ASSEMBLING YOUR OWN XT CLONE. . . . . . . . . . . . . . . .

ANNOTATED BIBLIOGRAPHY. . . . . . . . . . . . . . . . . . .



1. Buying a new computer can be a joyous event. . . . . . .
2. The first microcomputer with nonvolatile memory. . . . .
3. An early mainframe . . . . . . . . . . . . . . . . . . .
4. The computer business is becoming increasingly
competitive . . . . . . . . . . . . . . . . . . . . . .
5. Software piracy is a big problem . . . . . . . . . . . .
6. Leave yourself as much expansion room as possible. . . .
7. AT&T 6300. . . . . . . . . . . . . . . . . . . . . . .
8. Compaq Deskpro . . . . . . . . . . . . . . . . . . . . .
9. Epson Equity . . . . . . . . . . . . . . . . . . . . . .
10. IBM PC Jr. . . . . . . . . . . . . . . . . . . . . . . .
11. IBM XT . . . . . . . . . . . . . . . . . . . . . . . . .
12. IBM XT Mother Board. . . . . . . . . . . . . . . . . . .
13. XT Clone Mother Board. . . . . . . . . . . . . . . . . .
14. IBM AT . . . . . . . . . . . . . . . . . . . . . . . . .
15. Kaypro PC. . . . . . . . . . . . . . . . . . . . . . . .
16. Leading Edge Model D . . . . . . . . . . . . . . . . . .
17. Tandy 1000 . . . . . . . . . . . . . . . . . . . . . . .
18. Tandy 1200 . . . . . . . . . . . . . . . . . . . . . . .
19. Apple IIe. . . . . . . . . . . . . . . . . . . . . . . .
20. Apple IIc. . . . . . . . . . . . . . . . . . . . . . . .
21. Apple MacIntosh. . . . . . . . . . . . . . . . . . . . .
22. Commodore 128. . . . . . . . . . . . . . . . . . . . . .
23. Commodore Amiga. . . . . . . . . . . . . . . . . . . . .
24. Read up on computers before buying . . . . . . . . . . .
25. Keep a look out for good deals . . . . . . . . . . . . .
26. (no caption) . . . . . . . . . . . . . . . . . . . . . .
27. Computer shows are good places for bargains. . . . . . .
28. BIOS . . . . . . . . . . . . . . . . . . . . . . . . . .
29. An EPROM . . . . . . . . . . . . . . . . . . . . . . . .
30. 8088 . . . . . . . . . . . . . . . . . . . . . . . . . .
31. V-20 . . . . . . . . . . . . . . . . . . . . . . . . . .
32. Flip-top case. . . . . . . . . . . . . . . . . . . . . .
33. Power supply . . . . . . . . . . . . . . . . . . . . . .
34. Disk drives. . . . . . . . . . . . . . . . . . . . . . .
35. Floppy disk controller . . . . . . . . . . . . . . . . .
36. Multi I/O. . . . . . . . . . . . . . . . . . . . . . . .
37. Color graphics . . . . . . . . . . . . . . . . . . . . .
38. High resolution display card . . . . . . . . . . . . . .
39. Advanced graphics adapter. . . . . . . . . . . . . . . .
40. A high resolution monochrome monitor . . . . . . . . . .
41. A poor monitor is bad for the eyes . . . . . . . . . . .
42. AT-type keyboard . . . . . . . . . . . . . . . . . . . .
43. 5151-type keyboard . . . . . . . . . . . . . . . . . . .
44. 20 Megabyte hard drive . . . . . . . . . . . . . . . . .
45. A 20 Megabyte hard disk contains the equivalent
of 10,000 pages . . . . . . . . . . . . . . . . . . . .
46. Hardware for case. . . . . . . . . . . . . . . . . . . .
47. The mother board . . . . . . . . . . . . . . . . . . . .
48. Prepare the case . . . . . . . . . . . . . . . . . . . .
49. Proper positioning of mother board, power supply,

and drives. . . . . . . . . . . . . . . . . . . . . . .
50. Connect power supply to mother board . . . . . . . . . .
51. Connecting the floppy controller to floppy drive . . . .
52. External connections . . . . . . . . . . . . . . . . . .
53. Installing expansion cards . . . . . . . . . . . . . . .
54. User groups are an excellent way to learn
about computers . . . . . . . . . . . . . . . . . . . .
55. (no caption) . . . . . . . . . . . . . . . . . . . . . .


I wish to thank the following people who have assisted in the creation
of this book: Jean-Pierre Chelouche, Catherine Curtis, Harold Henderson,
Michael Epstein, Karen Rutsch, Nite Arios, Michael Judas, Jonathan
Becker, the members of the IBM XT Clone User Group of San Francisco, and
the many readers who have offered comments and suggestions. The
computer assembly illustrations were done on an XT clone using AutoCAD,
courtesy of Autodesk, Inc.

Information System, 431 Ashbury St. SF, CA. 94117 (11.95 postpaid)


In recent years, a tremendous number of companies have introduced
microcomputers onto the market. The consumer who is interested in the
best price, quality and performance available quickly realizes the job
of selecting a computer can become a sizable research project. One can
spend days, sometimes months, making sense out of the voluminous array
of information available. In this guide, I will demonstrate how, at
the present time, the IBM "XT clone" is the best microcomputer buy on
the market for individual or business use. The phenomenon of XT clones
is relatively new and not much information exists for the prospective
computer buyer. I hope this Buyers' Guide will be of significant
benefit to you in making your prospective purchase. I have tried to keep
this rather complex topic as simple as possible without being
simplistic. This I have hopefully accomplished by keeping three main
objectives in mind. The first objective is simply to share with the
reader my own personal view of how the present microcomputer market is
developing; a simple look at its development and a hint or two as to
where it seems to be going. The second objective is to take a
contrasting look at what microcomputers are on the market. And the
third objective is to offer a continuing reference for XT clone owners
who want to understand their computers better and who would like to
expand hardware capabilities themselves.

This guide was written and is continuously being expanded upon with
assistance from the members of the IBM XT Clone User Group of San
Francisco. Also the users of this guide have continually offered
suggestions that I have found especially helpful in rewriting and
updating. The user group here mentioned was the first computer user
group in the San Francisco Bay Area devoted entirely to the support of
IBM XT clones. The group can be reached care of the address listed
below, or via modem at data (415) 552-9070. The Computer Bulletin Board
Service (BBS) is on- line 24 hours a day, 7 days a week at 1200/300
baud. If while reading through this guide you find yourself asking
questions that aren't covered in the text or you come across additional
information that would be helpful to include in the next revision, I
would gratefully appreciate hearing from you via the previously
mentioned BBS or the address below. All significant contributions will
be repaid with a free updated version of this guide.

Edwin Rutsch
431 Ashbury Street
San Francisco, CA 94117
(415) 552-86485

Information System, 431 Ashbury St. SF, CA. 94117 (11.95 postpaid)


Since buying a computer can be a complex and frustrating endeavor, it
might help if your choice is grounded in some degree of knowledge about
the microcomputer industry---its overall development, its standards, and
the volatile nature of this complex industry where companies rise and
fall so quickly and oftentimes, dramatically so. This general
understanding of the computer industry might in fact help prevent you
buying a computer that is out-of-date even before you buy it. The first
microcomputer with nonvolatile memory.

The microcomputer industry started coming of age in the late 1970s with
the first pioneering companies. During that time and into the early
'80s, there developed two main standards for microcomputers. The first
was Apple, and the second was the CP/M operating system.

Apple owed much of its success to being one of the first microcomputers
on the market, but also very much to the fact that its computer was
easily expandable due to its "open architecture" (user-accessible
expansion slots). Its easy expandability allowed third party

manufacturers to create add-on features which, in turn, increased the
usefulness of the machine and reinforced the strength of the computer in
the marketplace.

Meanwhile, the CP/M operating system became the standard for several
microcomputer manufacturers, including Morrow, Osborne and Kaypro.
Within time a two layer microcomputer standard developed, with Apple
being the standard for home and school uses, and CP/M serving the
business market.

In early 1981, IBM, the world's largest computer maker, introduced its
own microcomputer, the IBM PC. Due to IBM's size and computer
experience, the IBM PC and its new PC-DOS operating system quickly
became the de facto microcomputer standard, especially for the business
market. In 1983 IBM introduced the IBM XT microcomputer. XT is
actually a name drawn from the word "eXTra." The XT is similar to the
PC, except that it has eight expansion slots (versus the PC's 5) and a
135 watt power supply (the PC has a 60 watt supply). The XT, therefore,
allows more expansion and has the wattage to power up to four data
storage devices---floppy disk drives, hard disk drives or tape back-up
systems---versus the PC's two. The XT initially came equipped with a 10
megabyte hard disk and was targeted especially for the business
microcomputer user.

Most other microcomputer manufacturers saw the writing on the wall:
either adopt the IBM standard or face going out of business. So they
began to develop and sell computers that were software compatible with
IBM. Hence the class of computers referred to as "compatibles" was
born. Compatibles can run most of the many software programs written
for the IBM PC and XT, although they are not totally hardware
interchangeable with IBM computers.

Like the initial Apple II series, the IBM PC and XT have open
architecture. This design has allowed a new industry to develop add-on
parts for the PC and XT. Whenever someone has the idea for a new
computer application, an expansion card that will perform that
application is developed within the basic framework of the PC and XT.
Examples are: modems for telecommunications; cards to make the computer
act as an answering machine; cards for connecting the computer to a
video cassette recorder (VCR); a new higher resolution video card, and
even a card to integrate the computer with a cash register. The list
grows daily.

In 1985, a new class of computers referred to as "XT clones" was
developed out of the add-on industry. This class now dominates computer
shows, advertising space in a growing number of computer publications,
and sales space in an increasing number of stores. In addition to add-
on cards, parts manufacturers began producing copies of each of the
component parts which make up an IBM XT. These parts may be assembled
into a computer which is a virtual copy of the original XT; hence the
name "XT clone." Every part of an IBM XT is completely interchangeable
with an XT clone and vice-versa. The IBM XT was chosen to copy because
of its greater expansion capabilities over the IBM PC.

The XT clones appeared in mid-1985 and are starting to profoundly affect

the computer market by helping to enforce not only the IBM software
standard but, more importantly, IBM microcomputer hardware standards.
XT clones are also dramatically lowering computer prices and thereby
threatening "compatibles" makers such as Compaq, Epson, Leading Edge,
Kaypro and Tandy. The XT clones are not a single computer but a set of
standards on which a large number of computer parts manufacturers have
agreed. This makes them fundamentally different from the compatibles
mentioned earlier because the compatibles are not totally hardware
interchangeable with the IBM XT. The XT clones come primarily from Asian
manufacturers who are doing what they are famous for, which is the mass
production of low cost, high quality electronic parts. Although many of
the parts for XT clones are manufactured in the United States, what
typically happens is that an American manufacturer will develop a new
add-on feature and, within a year or two, Asian manufacturers will begin
producing a low-cost clone of that part. The XT clone phenomenon has
contributed greatly to the rise of a world-wide microcomputer hardware
standard based on the IBM XT. I refer to this standard as the "XT

How will the microcomputer industry develop in the next several years?
As I see it, the XT standard will continue to grow and dominate the
world microcomputer market. The dominating company will continue to be
IBM, because there is no computer or manufacturer on the horizon which
can challenge the standard that IBM imposes. In the foreseeable future,
the only company that could do battle with IBM is AT&T and, for now,
AT&T is following IBM's computer design precedents. There will be more
clones and compatibles arriving on this already overcrowded market,
pushing prices lower and making life progressively more difficult for
compatibles manufacturers. Due to the XT clones' growing acceptance,
low cost, high software compatibility and hardware interchangeability
with the IBM XT, they will become the microcomputer of choice.

The XT standard is not likely to change very rapidly. This is
especially true when taken in consideration with the momentum of the
hardware and software in existence and how thoroughly the PC and XT have
permeated the business environment; they are now entering educational
institutions (traditionally Apple's domain). Schools are beginning to
realize that when students graduate, many will be entering business,
which is dominated by IBM computers.

The flexibility of the XT standard should also insure a significant life
expectancy for the XT clone. This computer's expansion capabilities
allow it to grow according to the individual's or company's needs. Big
business is known for its slow and cautious moves and it is not likely
to change its microcomputer standard rapidly, especially considering the
huge financial investment made in IBM hardware, software and training.

What is likely to happen is that bigger businesses, which may need
multi-tasking, easier network capabilities and greater speed than the XT
standard offers, will move up to the IBM AT standard microcomputer.
This is IBM's next most sophisticated microcomputer, above the XT. The
soon-to-be-released IBM AT 2 (or whatever it will be called) will be
another option for this market. This scenario will take place as the XT
standard and compatibles continue to move into the small business,
education and home user markets.

The large installed base of PCs, XTs, compatibles and XT clones insures
that software and technical support for the XT standard will continue.
Also, the fact that IBM maintains some compatibility to this standard
with its newer and more powerful microcomputers adds to the standard's
continued viability. The overall pattern that has emerged for the
microcomputer industry is clear: IBM sets the standards and the
compatibles and clones follow close behind. The AT clones are dropping
rapidly in price and are becoming ever stronger contenders. It is
rumored that IBM does not worry about competition from the compatibles
manufacturers, but is very leery of the overseas clones. With low
prices and high compatibility, the clone makers have found a unique way
of getting a firm foothold in the U.S. as well as the world computer
markets. It is significant to note that these manufacturers are making
powerful computers affordable for ever increasing numbers of people.

Information System, 431 Ashbury St. SF, CA. 94117 (11.95 postpaid)


The following analysis will make it clear to a prospective computer
buyer that the XT clone is perhaps the best microcomputer buy available
today. First, we will look at reasons why the XT clones are an
exceptional bargain; then we'll review some of IBM's own microcomputers,
major name brand compatibles, and some of the major non-compatibles on
the market.


1. XT Clones Have a Maximum Selection of Commercial Software.

The largest library of commercial software is available and continues to
be written for the IBM PC and XT. For legal reasons, neither the
compatibles nor the clones may be 100 percent software compatible with
IBM (though many advertise that they are). The XT clones, however, rank
among the most compatible of computers with IBM software. If
compatibility problems arise, XT clone computers have the greatest
flexibility for changing what is known as the Basic Input/Output System
(BIOS) for another BIOS which may solve the problem. (BIOS will be
explained in greater detail later.)

2. XT Clones Have a Maximum Selection of Public Domain Software.

Many software writers place their software, written for the IBM
standard, into the public domain. This means their software may be used
freely by anyone. There are user groups and other organizations which

compile these programs into libraries that are available for the general
user. Users typically pay a small fee for each disk of this software.
Many low cost software programs are also available under the "shareware"
concept---this software is freely distributed and if you use and like
it, you are asked to send the author a payment of $20 or so. There are
many fine programs available in the public domain, and many can be
downloaded (transmitted electronically over telephone lines and received
by your computer) from computer bulletin boards. These programs include
word processors, data base managers, games, educational and
telecommunications programs, and utilities. XT clones have the ability
to use almost all of these programs.

3. XT Clones Do Not Typically Have Unneeded Bundled Software Included.

Manufacturers and dealers who sell clones do not usually "bundle"
(include free) software with their systems. The operating system is
generally not included in the purchase price as it is with many of the
compatibles---it must be purchased separately, which adds about $70 to
the price. Many compatibles come bundled with other software such as
word processing and data base programs. Generally speaking, these
programs are not very desirable and often are being "dumped;" similar
software can be found in the public domain for a very nominal cost. Not
receiving bundled software can be advantageous; you buy your hardware at
rock bottom prices and then choose the ideal software for your
applications freely. You don't wind up paying a hidden extra charge for
a "bundle" you might never use, so in the end you may save money.

4. XT Clones Have the Greatest Flexibility for Custom Designing Your
Computer System to Fit Your Needs.

Because the XT clone is not one computer, but a set of individual
subassemblies, it is possible to choose the individual subassembly which
best suits your needs and pocketbook. There are hundreds of companies
which make their own versions of each part, so buying a clone can be
likened to a smorgasbord. You can buy the keyboard you like or the
monitor you like. You can choose expensive, high quality parts, or buy
lower cost components and upgrade later. It is also possible to choose
unique improvement parts like "turbo" mother boards which significantly
speed up the operation of your computer.

5. XT Clones Have a Large Interchangeable Parts Capability.

Aside from the ability to run most software written for the IBM
standard, perhaps the second biggest advantage of the XT clones is that
all parts are interchangeable with the IBM XT and the XT standard. This
means parts are readily available and will continue to be available
simply because of the huge installed base of these computers. One
factor to consider when you contemplate the purchase of a compatible
like those from Epson, Leading Edge, Kaypro and the rest is that with
computer competition so tough, there is a good chance a compatible
manufacturer may be forced to drop or change its line because of low
profits or sales. The market is being flooded with both compatibles and
XT clones, causing stiff competition among compatible and XT clone
dealers; many of them will not be able to survive. When you buy an XT
clone, the advantage is that even if the specific manufacturer or dealer

goes out of business, parts for clones are so common and inexpensive,
you'll be readily able to find replacement parts, service and expansion
accessories at a reasonable cost. On the other hand, if an IBM
compatible computer line such as one of the ones mentioned in this guide
were to go out of business, you might end up needing specifically
engineered parts for replacement which could be difficult or very
expensive to get. If a line is discontinued, the dealer from whom you
purchased the computer will probably not want to tie up capital in spare

Many people respond to this by saying, "Ah, but Epson, Leading Edge,
Kaypro, etc. are very large companies. They are not going to drop their
lines of computers." But well-known companies dump models all the time.
Epson has dropped the QX-10 and QX-16; Leading Edge has discontinued its
Model M; IBM is no longer manufacturing the PC or the PC Jr.; Kaypro
dropped its CP/M machines; Apple scuttled the Apple III---to name a few.
The list most surely will continue to grow.

6. XT Clones Have Excellent Expansion Capabilities.

The XT clones have eight expansion slots and a 135 watt power supply
(sometimes more powerful), which allows for a lot of growth. Many other
computers do not have this expansion capability. It is a good idea to
leave yourself ample open expansion slots to be able to take advantage
of new applications.

Often computer sales people will tell prospective customers, Three
expansion slots is enough, and two drive slots---one for a floppy drive
and one for a hard disk---that's all you will ever need." But this
ignores the many new applications being developed which require
expansion cards (and slots) and/or extra drives.

7. XT Clones Have a Readily Available Add-on Capability for Newly
Developed Hardware.

New software, and new add-on cards and peripherals, now generate more
excitement than new basic models of computers. New hardware add-ons
which work within the framework of the IBM PC and XT are a frequent
(almost daily) development for this standard. With an XT clone, it is
possible to take advantage of all these new add-on features---which is
not necessarily true with compatibles. (An example is the new IBM AT-
compatible mother board, which is the same size as an XT mother board.
This means owners of XT clones can upgrade their computers to the
capabilities of the IBM AT by simply swapping mother boards. This option
is not yet possible with compatibles.)

8. XT Clones Generally Are Made With Quality Parts.

Generally speaking, the quality of XT clones is very good. Clones are
sometimes scoffed at because of their Asian origin, yet Asian
manufacturers make some of the best electronic equipment in the world---
many of the components in IBM computers are also made in Asia. Almost
every day, you read in the newspaper of another computer maker moving
its manufacturing facilities to Asia. The wide variety of available

parts means that, of course, there are a few low-grade computer parts on
the market. This guide is designed to assist you in getting the best
parts for your money. Chapter 4 covers what to look for (and look out
for) when buying parts.

9. XT Clones are the Least Expensive and Easiest to Repair.

Because parts for XT clones are readily available, and most fit and work
the same way from model to model, the clones are very easy and
relatively inexpensive to repair. All repair shops which can repair IBM
computers can repair clones, because the parts are all interchangeable.
The vendor from whom the clone was purchased probably also can repair
it, if trouble arises. You can also repair your XT clone yourself,
by simply swapping parts until you determine which one is bad. New
parts can be ordered by mail or bought from dealers and computer shows.

Many clones come with an easy access flip-up case which makes repairs
simple and fast. Anyone can swap a few parts to determine which is
defective. Because parts are so inexpensive and labor costs are so
high, it is often less expensive to determine which part is bad and
replace it yourself. There is no other computer which has a greater
availability of replacement parts than the XT clone. Computer magazines
contain page after page of parts advertisements; at computer swap meets,
which are held often in most cities, there are booths upon booths
selling clones and parts. Clones and clone parts are also sold by more
dealers than any name brand computer.

10. Service Contracts are Not Needed for the XT Clone.

A sales strategy used by many large computer manufacturers is to make
parts for their computers non-interchangeable with other makes. In
researching information on computers other than XT clones for this
guide, I was amazed at how many parts were not interchangeable among
different models. Some manufacturers will sell you their basic computer
at a low price (still not as low as for an XT clone), then stick hefty
price tags on expansion and repair parts, labor and other service
charges. Tandy and Commodore, for example, have become notorious for
this. An option offered by some name brand computer companies is a
costly insurance policy the purchaser may buy, called a Service
Contract, ostensibly to protect his or her large investment. Because
clones use low-cost, interchangeable parts and are easy to self-service,
a service contract is an unnecessary expense. Many corporate
microcomputer buyers are reluctant to buy XT clones because they may
worry about future service. What they are overlooking is that they
could purchase two or three XT clones for the price of one IBM XT. This
means they could have a complete replacement computer immediately
available if one unit should fail. For the price of a one year service
contract they could purchase still another XT clone.

11. Support for an XT Clone is No Better Or Worse Than For Any Other

One major complaint about XT clones is that support is minimal. Often
clone dealers sell their products as if they were commodity items like
hats or vegetables, and dealers themselves may have only a little

technical understanding of computers. This complaint, however, could be
directed at any computer dealer and is not necessarily true only of
those who sell clones. It is actually possible to get more support from
a clone dealer than from one that sells IBM or compatibles. There are
certainly unethical dealers selling clones, as there are for any
computer. When choosing dealers, you have to be careful. The
operations of the hardware are fairly straightforward. Where most users
need support is in running software, and in this case the responsibility
for support is with the vendor from whom it was purchased. In any case,
there are many excellent books available to assist users in operating
their computer hardware and software. In fact, the many books written
about the IBM PC and XT can be used directly in understanding the XT
clone. There are also many computer user groups which support IBM and
clones, as well as groups specifically for clone users.

12. Long Warranties Are Available for XT Clones.

For people who feel more comfortable having an extended warranty---one
longer than the industry standard 3 months (IBM's warranty)---there are
clone dealers who will provide warranties of a year or longer.

13. XT Clones Are The Lowest Priced Powerful Computers Available.

For most buyers the central question is, "Can I afford it?" Perhaps the
greatest advantage for most people in buying XT clones is that their
prices are significantly lower than any comparable computers on the
market. Clones are much less expensive than IBM computers, somewhat
lower priced than compatibles and usually less expensive than fully
configured low budget computers such as Commodore, Atari, etc. [TABLE]

Information System, 431 Ashbury St. SF, CA. 94117 (11.95 postpaid)


In this section, I will review many of the popular "name brand"
computers on the market.

AT&T PC 6300

Lately, the AT&T PC 6300 has been heavily discounted, but it's still at
least $1,000 above the price of a comparable XT clone. The PC 6300,
however, uses the 8086 microprocessor (the IBM PC and XT, as well as XT
clones and compatibles, use the 8088 microprocessor), so it's a true 16
bit computer and therefore has a faster operating speed. The problem is

that 16 bit cards which work on the IBM AT, which is the industry
standard for 16 bit microcomputers, don't work on the PC 6300, and there
is a shortage of 16 bit cards that do work on the AT&T. This shortage
exists because few third party distributors are supplying accessories
for the relatively small 8086 market. An enormous array of vendors,

cards and interfaces exists for the 8088 PC, XT and compatibles market.
Again, the advantage of the PC 6300 is that it works at a faster speed
with its 8 MHz option, so you can switch from 4.77 MHz to the higher 8
MHz speed. In response to that, however, the XT turbo mother boards are
available for XT clones, which run at 4.77, 6, 7 or 8 MHz, for a much
lower price than the AT&T.

Virtually none of the standard parts on the AT&T are hardware
interchangeable with the XT standard. This is true of the monitor,
power supply, keyboard and mother board. That doesn't leave much to
interchange, except the expansion cards. AT&T will have a PC 6300
purchaser virtually locked in with regard to service and expansion, and
you can be sure costs for these items will not be low. It's also
impossible to install a better keyboard from among the many choices
available for XT standard. The keyboard that comes with the AT&T has
the same poor layout as that of the IBM PC, except that it does have
LEDs on the "CAPS," "Number Lock" and "Scroll Lock" keys.

Compaq Deskpro

The Compaq Deskpro is one of the better compatibles available. It has a
high degree of compatibility with the IBM XT, just as do XT clones. The
price of the Deskpro is, however, just slightly lower than the IBM XT
and much higher than a comparable XT clone. A disadvantage of the
Compaq is that its mother board is a different size than XT standard so
it is not hardware interchangeable; if something goes wrong with the
mother board it must be replaced with a Compaq part. The same goes for
the Deskpro's large 200 watt power supply. The mother board does take
640K worth of memory chips directly, which is a good feature.

I hear many good things said about Compaq. It's a serious company and
the computer shows professionalism. Its chassis is better made than low
cost XT clone chassis, which are sometimes a little sloppy in execution
(for example, clone screw holes and slots don't always fit precisely and
may need some manual adjustment). The clones are made at high speed
with medium precision machining while Compaq is more precise, but you
pay a high price for it---almost two and one-half times that of an XT

Epson Equity

Epson finally has made a true IBM compatible. They were very slow to
enter this market, perhaps because they had really bad luck with their
previous QX-10 and QX-16 models (which have been discontinued). Those
computers basically were failures, so Epson's reputation for
microcomputers has suffered. However, they're known for their high
quality printers, and their IBM compatible is certainly a respectable
entry. It's called the Epson Equity 1.

The Equity 1 is very much like Leading Edge's Model D---the same size
and basic style. Its mother board occupies the whole chassis and
contains the floppy drive controller and both serial and parallel ports.
Almost all the circuitry is on the mother board, including up to 512K

memory. It could become very expensive if something goes wrong on the
mother board, which is not in keeping with the XT standard and might
need to be completely replaced. Epson service is priced high. The
Equity's stylish case is smaller than XT standard. It has a smaller
footprint, thereby taking up less room on your desk, an advantage. A
related drawback is that you don't have as much room for expansion.
There are only 3 expansion slots, which really is a limiting factor.
Also, there are only 2 half-height drive slots so you can't have two
floppy drives, a hard disk and a tape back-up installed internally.
Mounting all drives in the computer helps to keep the cost of the
accessories down and keeps the hardware compact. The Epson's power
supply is an anemic 53 watts which, again, doesn't allow for much
expansion. The keyboard has a fine layout but unfortunately no LED
status lights for the "CAPS," "Number Lock" and "Scroll Lock" keys.
The main drawback with the Equity 1, therefore, is its cramped expansion
capabilities. Once you add a hard disk with its controller and an
internal modem, for example, you're left with only one expansion slot.
The Epson's price is also higher than the price of an XT clone (which
has much greater expansion capabilities).

IBM has done a great service to the microcomputer industry and the
consumer by bringing to the market the PC, XT and AT microcomputers with
open architecture. By doing so they set a standard for other
manufacturers to follow. The benefits to users are obvious. The major
benefit is a single uniform operating system which leads to lots of
interchangeable software.

And with a large market, the price (theoretically, at least) is lower.
Open architecture has opened the door for third party manufacturers to
create new applications, all of which work within the same basic
hardware framework. Again, with standardization and mass production of
hardware the price falls and computers become more affordable to more

This is not at all to say that IBM hasn't faults---far from it. I've
met enough computer buyers who, when they hear the name IBM, listen to
hear angels sing. They have taken "Big Blue's" slick advertising
seriously and think IBM makes no mistakes and is the personification of
goodness, motherhood and apple pie rolled into one. The truth of the
matter is that IBM is just as potentially fallible $and just as
interested in getting your money as is the next computer company.
In the next several pages we will take a look at the microcomputers that
IBM has been marketing with huge success, mostly because it is the
dominant computer maker in the world market and not necessarily because
its computers offer superior quality or innovation.


The PC Jr. is the bottom of IBM's microcomputer line and the computer
with which they once hoped to enter the home user market. It is an
unwise purchase. IBM has stopped manufacturing it, which means that
support will slowly be disappearing. There will be little software, and
replacement parts will be expensive and hard to get. The PC Jr. has a

poor keyboard layout, with the numeral keys also serving as function
keys. The PC Jr. is also significantly slower in operation than the PC
and XT.

Computer dealers are selling the PC Jr. at liquidation prices. Many
people must think they're getting a real bargain with the PC Jr., until
they try to do any sort of expansion. If you want to add a second disk
drive, it will cost over $300, whereas a second drive for an XT clone
may be added for under $100. The PC Jr. has no expansion slots, so any
accessories must be added externally, an expensive option. With
everything considered, a reasonably configured PC Jr. costs about the
same as an XT clone but without the clone's faster speed, open
architecture and other superior capabilities. This computer has
seemingly been a boondoggle for IBM, and IBM is now merely unloading it.

The IBM microcomputer next in capabilities above the PC Jr. is the IBM
PC. Like the PC Jr., it is now no longer being manufactured. As
mentioned earlier, the only real difference between the PC and the XT is
the XT's greater expansion capabilities. The XT has 8 expansion slots
and a 135 watt power supply, compared with the PC's 5 expansion slots
and 60 watt power supply. Why IBM didn't just offer the XT originally
is anybody's guess, because the cost of the extra power supply wattage
and three more expansion slots is negligible.

The PC and XT standard will be around for a long time, which means many
new hardware features will be developed for them. New features may take
up one or more expansion slots; the five slots of the PC will quickly be
filled. Due to the rapid development of add-ons, it is advisable to
leave yourself as much room as possible for future expansion. Even if
you don't need extra capabilities now, down the road---after you've
mastered your equipment---you'll want to get the most out of your
investment and that's done by using the computer for new applications,
which often require an extra slot.

Since the PC is otherwise so similar to the XT, much of what is
mentioned in the next section about the XT applies to both.

Information System, 431 Ashbury St. SF, CA. 94117 (11.95 postpaid)


Superior to the IBM PC in expansion capabilities is the IBM XT, which
initially was marketed with a hard disk installed and, as mentioned
earlier, was aimed especially toward business users.

The XT can now be bought without the hard disk drive. Because the IBM
XT is the standard on which XT clones are copied, I'll go into a
significant amount of detail as to how the IBM XT compares with the XT

The word "clone" means an exact copy of the original. This is not
always 100 percent the case with XT clones due to copyright laws, but
the clones do come extremely close to the IBM. This is possible because
all the parts which make up an IBM XT, except for the internal code in
one chip, are generally available, off-the-shelf parts which anyone can
freely buy.

IBM was out-smarted and out-maneuvered by the clone makers; not only are
clones able to run virtually all the software written for the PC/XT, but
they are in many ways superior. The Japanese experience shows how
imitation and commitment to detail can lead to high quality, innovative
products, which is exactly what happened with the XT clones. The clone
parts manufacturers are small companies which bend an attentive ear to
the wishes of the market. They rapidly change and improve their
products according to users' desires and latest technologies. On the
other hand, large, slow-moving IBM takes an incredible amount of time to
get something changed or improved.

IBM does, however, address problems which come to its attention, if
rather slowly. In April 1986, IBM announced several hardware and
pricing changes to its microcomputer product line which increase its
competitiveness in the market. The changes were not innovative, but
were designed to catch up with features its competitors were offering.
In the following pages the individual parts of the XT clones will be
compared to their IBM counterparts: A. The Mother Board The mother
boards of the IBM XT and the XT clones look very similar. They use most
of the same chips and the workmanship appears to be of the same quality.
Mother boards of XT clones have some different features than the XT:

One chip, the Basic Input/Output System (BIOS), is the critical part
which determines software compatibility with IBM and determines which of
the thousands of programs written for the IBM will run on a clone or
compatible. The BIOS is on a microchip called an EPROM (for Erasable
Programmable Read-Only Memory). This EPROM can be compared to a cassette
tape: any program may be copied onto it and used. It is also possible
to erase the contents of the EPROM (using ultraviolet light) and to copy
a new program onto it. In essence, the BIOS is the (erasable) program
contained in this one chip. This program is what controls the
operations of the computer and peripherals.

IBM jealously guards its BIOS and won't sell it to anyone unless they
buy IBM's whole computer. If IBM would sell their BIOS alone, it could
be added to an XT clone and you would have, literally, an IBM XT. But
it is possible to "burn" your own BIOS which is similar to making a copy
of a cassette tape or floppy disk. The process takes three or four
minutes with a device known as an EPROM burner. EPROM burners are
available for under $100, and you may also use one at some computer
parts stores where they have EPROM burners available to the public. The
cost of a blank EPROM and the rental of a burner at one of these stores
is under $5. Burning the EPROM only involves placing an IBM BIOS into a
socket and a blank EPROM into the socket next to it. Then the EPROM
burner copies the contents of the IBM BIOS onto the blank EPROM by
burning new pathways through the silicon.

Under U.S. copyright law it is illegal to do this, so what clone
manufacturers have done is write their own BIOS as close as legally
possible to IBM's. There are many different legal BIOS's available.
The Taiwanese government wrote one, and after completion they submitted
it to IBM, which acknowledged that the Taiwanese BIOS did not infringe
on the copyright. This BIOS has been licensed to many small clone
manufacturers which did not have the resources to write their own
versions of the IBM BIOS. The Taiwanese government's motivation was to
help stimulate the clone industry in that country. There are many other
versions of IBM's BIOS available; some have been written in the U.S. by
companies that sell XT clones, and others by large overseas companies
that make clone XTs. All the BIOS's are fairly compatible with IBM's,
although some are better than others.

With either clones or compatibles, it is possible that you may come
across a program that does not work with your specific BIOS. With XT
clones, however, you are not locked into having to use only the BIOS
that came in your computer. You can purchase a different company's BIOS
and it is a simple plug-unplug task to install it. I must reiterate
that most BIOS's will run most of the software on the market, especially
the more popular programs.

The clone BIOS's have some advantages over IBM's---mainly in speed. The
IBM BIOS takes a long time to do its initial memory self-check, a
feature of all BIOS chips, and it's irritating to sit in front of the
computer after it's turned on to wait for the BIOS to be ready for your
work. Most XT clone BIOS's zip right through their memory checks.

2. 640K Mother Board
An advantage that XT clones had over IBM's XT for about 6 months was
that it was not possible to install 640K directly on the IBM mother
board. IBM has since rectified that problem with a new mother board
design, but there are still some of the old version out there. Placing
640K (the maximum the XT can directly address) on the mother board makes
the memory more compact, uses fewer chips, gives off less heat and saves
one expansion slot.

3. Turbo Boards
One of the latest developments for the XT clones is the turbo mother
board. The clock speed of the IBM XT is 4.77 MHz. With a turbo board
in an XT clone, it's possible to get 60% faster operation with
switchable 4.77 to 8 MHz speed.

A difference among IBM, the clones and compatibles is that IBM places
the BASIC programming language on 4 ROM chips. That means BASIC is
available from within the computer without your having to load it from a
disk. Since IBM has a copyright on its BASIC, no other computers have
this built-in feature. This is not a significant advantage, however,
since generic BASIC (GW-BASIC) is available on disk like any other

B. Drives
IBM has finally switched from the bulky full-height, belt driven floppy

disk drives to half-height drives for the XT. XT clones, on the other
hand, were using half-height direct-driven floppy drives for at least a
year previously.

C. Case
Most XT clones are offered with a flip-up case. This makes access to
the inside easy and has the effect of helping to demystify the working
parts of the computer for the user. IBM uses a slide-out style case.
Clones may be bought with the slide-out case as well, if desired,
although the flip-up case is not an IBM option.

D. Keyboard
A major complaint among IBM XT users has been its poorly designed
keyboard. This problem has finally been addressed with a very nice
keyboard now offered by IBM. But the clone makers are still a step
ahead, with keyboards that can be used on both the XT and the AT---a
desirable feature for those who will want to upgrade to an AT system
later. E. Monitor The high resolution monitor that can be purchased from
IBM for the XT is offered only in a green screen color, a major drawback
because green-phosphor monitors leave a distracting after glow or
"ghost" image on the screen after text or graphics have been turned off
or moved. Amber monitors available with most clones do not suffer this

F. Price
When IBM announced its recent hardware improvements (or catch ups), it
also lowered its prices. This, however, prompted the clone makers to
lower their prices in an effort to remain competitive. With the price
structure that has emerged, an XT clone generally costs about 50 percent
less than a similarly equipped IBM XT. Price, as well as better
hardware features, are the dominant reasons to buy a clone rather than
the original IBM XT.

Information System, 431 Ashbury St. SF, CA. 94117 (11.95 postpaid)


The next computer in IBM's line above the XT is the IBM AT. The AT has
more features than the XT; namely: greater speed, more storage,
multitasking capabilities, and a hefty price---over $4,000. This
computer is becoming the standard for businesses that want multitasking,
need high speed for manipulating large amounts of data, or are involved
in system development. The IBM AT is especially geared for businesses
that want a network of computers in the office.

A number of AT compatibles have come onto the market, and so have AT
clones. AT clones, like AT compatibles, are still relatively expensive,
although their price is falling rapidly. At present, the AT is not
really a machine for the average user, but if you have a business, you
may want to look into AT clones.

One interesting feature I've seen lately is an AT clone mother board the
same size as an XT mother board (generally it's much larger and needs
the mammoth AT case). This is potentially extremely useful because it
means present purchasers of XT clones will be able to upgrade their
computers to ATs merely by adding a new mother board. Mother boards for
AT clones are still very expensive at over $700, compared to just over
$100 for an XT board. But the XT-sized mother boards for AT clones will
eventually fall to the prices of presently-priced XT mother boards, and
it will then be a simple and cheap conversion to gain all the advantages
of the AT. This will be a very cost effective way for XT clone owners
to upgrade without having to purchase whole new computers. (I'm working
on a Guide Book for the AT clones; so, if you have any experience with
them I'd appreciate it very much if you'd let me know. The address for
all correspondence appears at the beginning of this guide, in the
Introduction.)5 Kaypro PC

Yet another IBM compatible microcomputer available is the Kaypro PC.
This is a very nice machine. It looks on the outside like an IBM AT,
and on the inside, it's almost a clone of the IBM XT. But the
interesting thing about the Kaypro PC is that it can be upgraded to an
AT later, with an AT-style mother board which Kaypro promises to release
soon. This is a good idea---Kaypro is looking ahead and saying, "Let's
not make something that's going to be obsolete." The clone
manufacturers, however, are still a step ahead with the XT-size, AT
mother boards. Placing one of these mother boards into an existing XT
case would be preferable to Kaypro's idea because the XT uses less

The price for a Kaypro PC is significantly higher than that for an XT
clone, but the Kaypro comes bundled with lots of software and the clones
typically have none. Unfortunately, much of the software bundled with
the Kaypro is outdated. Software similar to what Kaypro offers can be
found in the public domain for a nominal fee. Clones still have the
best price/performance ratio and therefore are better buys.

Leading Edge Model M
Another microcomputer available is the Model M sold by Leading Edge, a
Massachusetts company known better for its software than its computers.
Leading Edge does not design or assemble its own computer products.
Their first offering, the Model M was manufactured in Japan by
Mitsubishi and sold under the Leading Edge name (it is also sold by
Sperry under that company's brand). Leading Edge and Mitsubishi have
had heated disagreements, ending in lawsuits, so Mitsubishi has stopped
shipping this model to Leading Edge, which has since found another
supplier (of a different machine) from South Korea (see Leading Edge
Model D).

The Model M is no longer produced and is being sold at clearance prices,
although these prices are still higher than for an XT clone. Because
the Model M has been discontinued, support and parts for it may be hard
to find, and there may be a long wait for repairs. Computer stores are
making "deals" on the Model M in an effort to dump it, but considering
the disadvantages, including a relatively high price, it is not
advisable to purchase this computer.

Leading Edge Model D

Leading Edge's new microcomputer is called the Model D. A very nice
machine, the Model D is similar to the Epson Equity 1, and it has the
same limited expansion capabilities. Not all Model D hardware can be
exchanged with the XT standard, so if Leading Edge goes out of business
it may be hard to get repairs. I don't mean to imply that Leading Edge
$will go out of business, only that such a possibility must be
incorporated into your computer shopping plans because Leading Edge has
always been on the "edge," so to speak. They are often undercapitalized
and they are a pushy, aggressive company. If they start having trouble
getting along with their supplier, Daewoo, they may end up dropping this
model as they did with the Model M.

At present, the Model D is selling very well, due in large part to a
favorable review in Consumer Reports Magazine's "Computer Buyers'
Guide." Leading Edge has waged a heavy advertising campaign around this
write-up. Consumer Reports, never willing to let its favorable reports
be used in advertising, has waxed furious and has even suggested that
buyers avoid the Leading Edge for this reason. But the good review has
helped tremendously in promoting both Leading Edge and its Model D.
There is a big flaw in Consumer Reports' "Computer Buyers' Guide," by
the way: XT clones aren't even mentioned. They should have at least
covered one or two of the "name brand" XT clones; that they did not
makes their guide look very out-of-touch and limits its utility for

Tandy 1000

Tandy Corporation (Radio Shack)'s best selling contribution to the
microcomputer market at present is the Tandy Model 1000. But the Tandy
1000 has lots of problems. It's a schlocky-looking machine in a case
made of cheap plastic. It has only 3 expansion slots and they are too
short (10 1/2 inches) for the installation of full length cards. So for
memory expansion you can't use a standard long memory card; you have to
install two of Tandy's short cards, which are very expensive. There is
no parity checking, a real problem because if there's a memory failure,
the program you're running will just lock up and you won't know why.
The Tandy 1000 has been offered at sale prices lately. It includes a
color monitor, but one which features very poor resolution. The Tandy
1000 costs more than a comparatively configured clone, but its quality
and capabilities are clearly inferior. There is no socket for an 8087
processor (with which the computer could be speeded up to do
mathematical computations).

There are slots for only two half-height disk drives. The keyboard is
not interchangeable with IBM standard; therefore you can't upgrade to a
better keyboard later on. And here's the real killer: if you open up
the computer within the warranty period, your warranty is voided.
Expanding a Tandy system could cost an arm and a leg---up to five times
that of XT clone accessories.

Balancing all the Tandy 1000's disadvantages is one advantage: there are

Radio Shack stores (and service) everywhere.

The stores, however, are usually not prepared to do repairs. The
computer will be sent to a service center, perhaps far away, taking a
long time to fix and not necessarily returning in better shape than when
you brought it in with its problem. As I said, this machine has lots of

Tandy 1200
Another microcomputer produced by Tandy is the Tandy 1200. It is a close
IBM compatible, using a Phoenix BIOS, which is what most of the
compatibles use. It comes with a 10 megabyte hard disk which is
outdated, due to the decreasing price difference between 10 and 20
megabyte hard disk systems (less than $100). A 20 megabyte hard disk is
a better buy. The Tandy 1200 comes in a metal case, unlike the Tandy
1000, but it has only five expansion slots (full length). Also, it uses
the inferior full-height disk drives. And---like the Tandy 1000---
Tandy's "don't-open-it" warranty policy is a problem. Despite its many
drawbacks, the Tandy 1200 is priced significantly higher than a better
equipped XT clone.


Apple IIe

Apple's most successful computer is the Apple Model IIe. This is
because of the IIe's many expansion slots, which allow it to be easily
expanded with accessories from third party manufacturers. The Apple IIe
is very practical. The cover pops off so you don't need a screw driver
to install or remove expansion cards. This is similar to XT clones with
their flip-up cases---I wouldn't be surprised if the idea of their flip-
top lids was inspired by the Apple IIe. This open architecture for
microcomputers was Apple's brilliant and successful idea in the first
place. They must be commended. The technology has raced ahead,
however, and left the Apple IIe behind. The IIe can directly address
only 64K of RAM, compared to 640K for the XT clones. The Apple's
keyboard is part of the case and therefore not detachable. It has no
numeric keypad, and no function keys. Besides many hardware drawbacks,
the Apple IIe cannot take advantage of the huge library of software
written for the IBM standard, which includes all the new and
sophisticated business programs.

There is a great deal of software written especially for the Apple,
especially in the area of education. Combined with Apple's policy of
selling computers at discount to schools, this has encouraged students
to use and buy Apples, and continues to assure them a large base of
young users. However, Apple is suffering now from loss of momentum with
their outdated IIe and their newer but less versatile IIc.

It's not a good idea to purchase an Apple IIe. Besides being
technologically outdated, it's unbelievably expensive. An XT clone with
ten times the capabilities can be bought for less than an Apple IIe or

IIc. Apple has carried out a heavy and persuasive advertising campaign
with their huge profits from selling overpriced computers, but what they
are selling is more imagery than substance.

Apple IIc
After the IIe, Apple moved incongruously toward a closed architecture
system with their Apple IIc. This means it is not possible to open up
the IIc (as you can the IIe) to add new features. This is ironic,
considering that Apple promotes itself as the computer for the people or
"the rest of us," casting IBM as a big, impersonal Goliath. The exact
opposite has happened. As Apple moved toward closing its architecture to
users, IBM has broken with long-standing tradition and opened the
architecture of its models to give the consumer more flexibility. Apple
has taken that flexibility away, possibly hoping to lock consumers into
buying only Apple accessories to increase its profits.

Besides having no expansion slots, the Apple IIc has the same drawbacks
at the IIe---limited RAM, outdated technology, nondetachable keyboard---
and a higher price.

Apple MacIntosh

The MacIntosh was Apple's effort to keep up with advancing technology,
launched to compete with the growing popularity of IBM and compatibles,
especially in business applications. But for the average computer user,
the MacIntosh is perhaps not a wise choice. It has many unique features
that make it easy to use---great graphics, use of icons, a high
resolution monitor. It's possible to sit down and play with a Mac and
quickly learn how it works. But there is a long list of MacIntosh

1. No color monitor.
2. The software for the MacIntosh is not compatible with any other
computer (even other Apple computers).
3. There is little good business software, and not a lot is being
4. It has no numeric keypad and no function keys.
5. Fewer Macs are in use than IBM standard models, which translates as
poorer hardware support and higher repair costs.
6. Like the Apple IIc, it is a closed architecture system, so expansion
is difficult, clumsy and expensive. Also, third party manufacturers are
discouraged from marketing expansion accessories. Opening a MacIntosh
system voids its warranty.
7. The computer and expansion accessories are costly.
8. No good word processing software is available.
9. The MacIntosh is very slow.
10. Its black-and-white monitor is very small. Although Apple has
promoted the MacIntosh as a business machine, it has never caught on for
this use and will not because of its drawbacks---and because business is
already committed to the IBM standard. Mac's innovative use of icons,
simple-to-understand software and the "mouse" are being incorporated
into programs written for IBM standard, thereby diminishing the few
advantages the MacIntosh had over IBM. Other computers, such as the

Commodore Amiga and the Atari 520ST are graphics-oriented (with color)
and have better keyboards and other features than the MacIntosh.

Commodore 128

A popular low cost computer is the Commodore 128. Discounted heavily, by
the time an external drive or two ($250 each) and a monitor have been
added the 128 costs as much as or more than an XT clone system, which
has much greater capacity. Commodore has been up and down financially,
down lately, and is rumored by some to be on the verge of bankruptcy.
This brings an element of uncertainty to the purchase of a Commodore

Commodore Amiga

Another microcomputer made by Commodore is the Amiga. This computer
features powerful color graphics, superior sound processing, great
animation capabilities, multiprocessing capabilities, and easy-to-use
icons. It comes with a single 880K disk drive; a second drive costs
$300. There are several drawbacks to this computer: first, all
expansion accessories are expensive. There is very little software
available and since the Amiga has such a small share of the market,
there never will be as much software written for it as for the PC/XT
standard. This is not a business machine and it never will be. It's
not a good idea to purchase such a computer until it has proven itself,
the bugs have been worked out, and more software has been written.
Even though the Amiga uses new and exciting technology and has great
potential, these days it takes more than great features to make a
successful computer. A computer line needs to be widely accepted so
lots of software is written for it and the price can fall via high
volume manufacturing. The de facto standard for microcomputers is IBM
because of its size and computer experience. IBM has been able to
virtually ram its standard down the microcomputer industry's throat. It
will be very difficult for any other company to set its own standard, or
even carve itself a niche, in the face of such competition, and there
are very few companies willing to take the risk of producing new
software for such a small market as the Amiga's; they're more interested
in the huge PC and MS-DOS market. The Amiga is selling moderately well,
but its future is shaky.


CP/M (Control Program/Microcomputers) was one of the first operating
systems written for microcomputers. Many of the early micro
manufacturers built computers based around this standard, but the CP/M
standard is dying out rapidly now, and it's not a good idea to purchase
a computer that uses it. Much more powerful XT clones can be bought
for, often, lower prices.

CP/M's major problem is that it can only address up to 64K of RAM. Many
of the newer, more powerful business programs need at least 128K to
operate; in addition, few games and graphic programs have been written
for CP/M because these programs are memory-hungry and need more than

64K. Support for CP/M is in a "free fall"---as hardware becomes less
common, no one wants to write software for it. I was invited to speak
recently at a CP/M user group meeting. Out of the 20 people there, six
or so already had bought XT clones and the others were considering it.
I often hear the argument that, for someone who only wants to do word
processing, an inexpensive (or used) CP/M computer is still a viable
option. I must disagree, because the new spelling checker and thesaurus
programs (which are real timesavers for writers) take more memory than
CP/M can address, and no one is trying to write these programs for CP/M
anyway. In the long run, it would be cheaper to get an XT clone rather
than buying a CP/M machine now and upgrading later. Note: For those who
have CP/M computers now, and want to switch to IBM standard without
losing all their files, there are file transfer programs that let you
convert CP/M files on disk to be read on the PC-DOS format.

Information System, 431 Ashbury St. SF, CA. 94117 (11.95 postpaid)


So you have now decided to buy an XT clone but are unsure where to buy
one. There are several possible routes to take, each with advantages
and disadvantages. I have grouped these choices into five categories:
Retailers, Clone Dealers, "Garage" Dealers, Mail Order Distributors and
Computer Swaps. If possible, I suggest you buy your computer from a
vendor near where you live, so you have easy access to service, support,
and the opportunity to develop a personal relationship with your dealer.
Whichever sort of dealer you buy from, follow a few general guidelines:

1. Know the exact terms of the sale, and something about your vendor,
before you buy.

2. Before buying, check the length of the warranty and how it is to be
honored. If a part fails, do you get a direct swap or does the part (or
the entire computer) have to be sent back to the factory for repairs? A
direct parts swap policy saves you down time.

3. How well do you get along with the dealer? Do you feel calm?

Don't buy if you feel pressured. There are many other vendors to choose
from. 4. Ask for the names and phone numbers of previous customers (if
they were satisfied with their purchases, they'll be more than happy to
tell you so).

5. Check the computer with software you want to run. Generally Lotus

123 is a good test for numerical processing capabilities, while Flight
Simulator gives graphics capabilities a good workout. Be sure the
programs you plan to use will run on the computer's specific BIOS---if
not you will need a different BIOS.

6. Get parts which will work with the AT, so you can upgrade later for
the minimum cost (parts to look out for are covered in Chapter 4).

7. It is possible to purchase a clone in parts or already assembled.
The savings from assembling your own computer are not very great, the
cost of assembly ranging from $30 to $70. The main reason for putting
together your own computer is to learn more about it and thereby gain
confidence and understanding. This will pay off later when you want to
expand or troubleshoot your system.

8. A growing issue with clones is that many have not been FCC approved.
The FCC has been cracking down on unapproved clones by issuing citations
and therefore dealers have scrambled to gain FCC approval for their
systems. A potential problem for owners of unapproved systems is that
legally, a dealer who sells computers without FCC stickers could be
forced to recall them. This could be an inconvenience, to say the least.
It seems advisable, when shopping, to keep this possibility in mind and
look for the FCC approval sticker.


Many computer retailers who carry IBM and other brand name computers
also sell XT clones. These tend to be independent stores; the large
chains such as Computerland and Radio Shack don't carry clones---yet.
XT clones come under a variety of names, often a store's own name. Some
widely-distributed models are getting to be called "brand name clones,"
many of which are heavily advertised.

Retail stores tend to charge the highest prices for clones. This is
because of their high overhead---rents, salaries, stock, etc. Some
buyers feel more secure buying from a retail store than from other
sources. Retailers offer a local source for support, parts, service,
advice and training in how to use the computer. They are often
knowledgeable about software while other sources may not be.

On the flip side of the coin, there are many retail stores where the
staff has minimal or no knowledge about their products.

Sometimes you may find you know more than the sales person (especially
after you've read this guide). Unless you can find a retailer who
offers exceptional service and support, it's usually preferable to buy
from one of the other, lower-priced outlets mentioned in this Chapter.

What I call "clone dealers" tend to be Asian, usually Taiwanese computer
dealers who sell clones and clone accessories almost exclusively. Their
places of business are typically small, a shop, office or house stacked
to the ceiling with boxes of computer parts. These dealers work with

low overhead; many import at least some of their parts directly from

A clone dealer's price for an XT clone will usually be lower than a
computer retailer's price for the same machine. This is because the
clone dealer does a high volume business and may import directly. There
are fewer middlemen and minimal overhead. Some clone dealers offer
little support beyond honoring the warranty, while others will offer a
great deal of support. Generally, the retail stores buy their clones
from clone dealers.

This means more middlemen, and higher prices. I have found that, in
general, clone dealers are quite responsible when it comes to supporting
the hardware they sell. They don't want to get a bad reputation which
would hurt their sales. If something should go wrong with the computer
within the warranty period, the clone dealer typically will immediately
replace it. This is especially true if they import the parts

The competition in selling XT clones has become increasingly tough and
is getting tougher. More clone dealers are setting up shop all the
time. At a computer swap in July 1985, I remember seeing only 3 dealers
who were selling XT clones, out of some 75.

At the next computer swap a month later, there were 15. The next month,
it seemed like everyone was selling clones. The same thing is happening
in the pages of computer magazines. At first, there were one or two XT
clones advertised; now there are multitudes. Anyway, this means there's
plenty of room for bargaining. This can be done by playing one dealer
against another: get a price quote from the first dealer, take it to the
second and ask if he can beat the first's price. It's very important,
however, to watch quality. Make sure the prices you're quoted are for
the same part or the same quality parts. If the difference is only a few
dollars, consider how far away the dealers are and buy from the one
that's most convenient to get to, in case of future hardware problems.
I don't mean to imply that a clone is more likely to fail than any other
computer; it isn't. The clones tend to stand up as well as any other
industry standard models.

The best place to meet clone dealers is at computer swap meets and shows
which are held every few months in most major cities. Also, check the
ads in the free tabloid computer magazines that are found in most
cities. Sometimes clone dealers advertise in local newspapers with
small display ads or, more often, in the classified ads under "Computers
For Sale." A typical clone dealer ad might read like these:

IBM XT compat. 640K, 1DD, $685. Unused warnty, (phone no.)

IBM XT compat. new w/warr. $699. 640K ser. par. clock $1299, all
upgrades avail. Call for price on AT! ABC (phone no.) GARAGE DEALERS

What I call "Garage Dealers" are the many individuals who have found
that they can assemble and sell XT clones from their homes, as a full
time job or as a sideline. Some are computer consultants who offer
advice---and clones---to their clients; some are students who sell to

fellow students and teachers. Some employees of large companies find a
ready market among their many co-workers. Some value-added resellers
buy basic clones or parts and customize them for buyers. And so forth.
Garage dealers often get into the field by first building an XT clone
for themselves, then for friends who want low-priced computers like it
and don't want to do the assembly. It doesn't take long and word-of-
mouth often is all a garage dealer needs to get established. Once the
garage dealer is selling a couple of computers per week, he or she can
go to the clone dealers for parts at "dealer prices"---and so work on
the same cost level as computer retailers who sell clones.

The number of garage dealers is mushrooming. Since there's no such
thing as an "authorized" clone dealer, as there is for IBM and other
name brands, the market is wide open for anyone to sell clones at any
price. Actually, this is one of the reasons for the success of the
clones. The market force of competition has helped to rapidly lower
consumer prices. Garage dealers can be found by word-of-mouth or in
the classified section of the newspaper. Their ads look the same as
those of the clone dealers.

The different personalities and personal situations of the garage
dealers make it hard to generalize about buying from them.

Since most garage dealers offer a three month warranty, your main
question becomes one of whether they'll be able to honor it.

The answer depends on three things: (1) the dealer's personal integrity,
(2) whether or not they'll be around in three months, and (3) whether or
not their supplier will be around to back them up. The volatility of
the computer market makes it hard to tell who will still be in business
tomorrow---even large computer manufacturers go out of business, and
large computer retail stores have been closing down recently, too. So
buying from a garage dealer is as secure or insecure a way to purchase a
computer as any other.

Some advantages of buying a clone from a garage dealer could include: a
more personal relationship; better consultation; greater support; custom
installation, etc. Because they work with virtually no overhead, it's
possible for garage dealers to remain competitive and viable sources for
an XT clone.

Information System, 431 Ashbury St. SF, CA. 94117 (11.95 postpaid)


In larger cities, computer shows and swap meets are held every few
months, or more often. Computer shows tend to be grandiose, with
seminars, product introductions, and flashy exhibits in big established
halls where manufacturers can show their wares. In such shows there
usually is a separate area for dealers who sell discount products. This
is where you will find the clone dealers. As a matter of fact, clone
dealers have virtually taken over the dealers' areas at shows and swaps.

Computer shows and swaps are about the cheapest places to buy an XT
clone. The prices come close to dealer cost level and amazing bargains
can be had here. This is primarily because of fierce competition, with
one booth next to another selling the same clones and clone accessories.
There is a wide variety of parts to choose from, so you have maximum
leverage to assemble a low-cost computer that exactly meets your needs.
Buying at a show or swap can be confusing. There are so many vendors
and parts to choose from. For the first time buyer, it is probably best
to buy all the parts for the computer from one dealer. This way if the
basic system doesn't work or should fail, you will know whom to return
it to. To determine what kind of organization is behind a dealer, get a
price quote and ask if they will maintain that price after the show. If
so, go to their place of business and check it out.

Often dealers will lower their prices toward the end of a show. This is
because they're anxious to sell, rather than repack and carry, their
show wares. Outdated and defective equipment that dealers don't want in
their stores is often unloaded at shows, so be careful. On the other
hand, dealers sometimes need quick cash, and may liquidate perfectly
good inventory at a show, offering you some very good bargains.

To find the location and dates of computer shows and swap meets, look in
local newspapers and especially free local tabloid computer magazines.


Buying a computer by mail order is a "blindfold on" affair, and you may
feel intimidated by the thought. But the mail order computer field has
become big business in America. Newsweek on May 8, 1986 observed that
P.C. Limited, of Austin, Texas, which is primarily an XT and AT clone
mail order house, sold $36 million in computers in 1985. Obviously a
lot of buyers are willing to trust mail order firms as legitimate and
trustworthy sources. Mail ordering a computer couldn't be simpler. You
just call (usually to a toll free number) or send in an order form, and
the U.S. Mail or a parcel service delivers a computer to your door in
what is usually a very short time. Mail order naturally appeals to
people who don't live near computer retail stores or other sources.
Mail order is not for every buyer. Typically, it is more appropriate
for the sophisticated buyer who is familiar with his or her own needs,
the product(s), and prices. Another person who can benefit is the
buyer---even a novice---who is stuck out in some remote place like Death
Valley, California and has no way to get to a convenient computer
outlet. For this buyer, ordering from a magazine coupon seems
reasonable indeed.

In general, the basic advantage of buying a computer through the mail is
price. Due to mail order firms' low overhead---no showroom, no sales
staff, no repair shop---they can offer the consumer rock-bottom cost.
Mail order firms also handle high volume, lowering cost. Some mail
order companies do direct importing of parts and machines, and therefore
their wholesale prices are lower, lowering your price. Even the so-
called garage dealers can't beat this, since they're too small to import
parts themselves.

Other advantages to ordering an XT clone by mail include the mail order
firms' typical wide selection; many makes and types of parts and
computers are available, as well as software, accessories, computer
books and more. You can shop from the comfort of your home, and enjoy
delivery to your home without the hassle of going from computer store to
computer store.

The basic disadvantage of buying your XT clone through the mail is risk:
you can't know what you are getting until it arrives. You may, for
example, get an especially noisy disk drive, a schlocky keyboard or a
noisy power supply that you could pre-test in a store and reject if it's
not right.

Another potential disadvantage is that there are sometimes hidden costs.
Two such possible costs are delivery charges and surcharges applied to
credit card purchases. Ask lots of questions when buying by mail order
and make sure the firm has a toll free technical hotline for help later,
if you have a problem with your purchases.

When buying mail order it's advisable to buy from a reputable firm.
Check back issues of such magazines as Computer Shopper, PC Magazine, PC
Week, InfoWorld, and Byte Magazine for mail order houses' ads. The
longer a specific firm has been advertising, the more reputable it is
likely to be. It's also a good idea to call the Better Business Bureau
office in the town where the firm is located to see if any complaints
have been filed against them.

Information System, 431 Ashbury St. SF, CA. 94117 (11.95 postpaid)



The advent of the XT standard means that there are multiple
manufacturers for each of the individual parts (or subassemblies) which
goes into the computer. For example, several different companies
manufacture mother boards. Many companies make monitors, many others
manufacture keyboards, and so on. With so many different sources, you
can expect a wide variety of features and levels of quality. Through
careful and informed shopping you can choose the individual parts that
are appropriate for your needs and budget.

Normally, eight different subassemblies are used to make up a
functioning XT clone. These are (1) the mother board, (2) the case, (3)
the floppy disk controller card, (4) the power supply, (5) disk
drive(s), (6) the keyboard, (7) the display card and (8) the monitor.
In this Chapter a closer look will be taken at each of the individual
parts needed for a functioning XT clone and some of the more popular

add-on accessories. All of the thousands of potential parts cannot be
examined here because of space restrictions and because there are so
many new add-ons coming on the market all the time. But we will focus
on the main ones now on the market. Unless you have a specific, highly
specialized application in mind, it's best to stay with the more common
parts because they're easier to replace, they cost less, and they're
manufactured in larger quantities.

As we examine each part, refer back to the section comparing the IBM XT
to the clones; some of the information there overlaps with this Chapter
and will help you to understand more.


The mother board is the central, main subassembly in the computer. It's
difficult to determine the quality of a mother board by looking at it;
generally speaking, if it works properly for the first three months (the
usual warranty period) then it is likely to keep working properly
thereafter. This is because integrated circuits (ICs or computer
chips), if they're going to fail, will usually fail right away. Those
that don't fail early in use will probably keep on working indefinitely.
Some things to observe on the mother board are the quality of the silk
screening and if the soldering work looks smooth and well flowed. The
solder joints should have a glossy wet look, no holes in the solder, and
no grey coloration. The ICs should all be well seated in their sockets
or connections and not be crooked or misaligned. There should be no
dirt or residue on the board and, of course, no cracks or deep

Some boards contain used chips. Sometimes, it's possible to find dates
on the chips to see when they were manufactured, but many manufacturers
strip out the date. In any case, chips have very long service lives and
used chips do not necessarily mean low quality or the possibility of
reliability problems.

On some mother boards, all the chips are installed in sockets (for easy
replacement), while on others some of the chips are soldered directly to
the board. All boards have sockets for the 8088, BIOS, EPROM and RAM
chips. Parts on mother boards are always interchangeable so a BIOS from
one could be exchanged with the BIOS from another, and so on. The
advantage of an all-socketed mother board is that chips can be easily
replaced; a disadvantage is that the chips' contact pins and the
contacts in the sockets can corrode, causing bad connections that could
stop the computer from working. It's a toss-up which is preferable: if
you are technically minded, get an all-socketed mother board so you can
repair it, if needed, yourself. The average user cannot easily trouble-
shoot a mother board, so it may be better to look for a mostly-soldered
board to avoid bad connection problems. If a mother board does fail,
it's normally cheaper to buy a replacement than to pay high labor
charges to repair it.

Parts of the Mother Board

Basic Input/Output System (BIOS)

The code written on the BIOS determines its compatibility to IBM
standard. The better the BIOS (the closer it is to IBM), the more
attractive the whole computer, because it can save you from the
unpleasant surprise of having a new program refuse to run. All the rest
of the parts can be bought off the shelf and are identical to IBM's.
The program written in the BIOS chip is the only part of the PC and XT
on which IBM has a copyright.


No compatible or clone computer is exactly like the IBM XT. The BIOS
must be somewhat different. So some programs may not run; if there is a
program you really want to run you can always exchange your BIOS for a
different one. One BIOS may run programs that another one won't run.
To change one from another is only a matter of pulling the old one out
of the socket and inserting the new one (in the same direction).


The central processing chip is called the 8088. It was designed by
Intel, and is used in the IBM PC, XT, most compatibles, and clones.
Recently NEC designed a new processor chip to replace the 8088; it is
called the NEC V-20. V-20


The V-20 is a replacement chip for the 8088, and has some improved
features. The V-20 contains twice the amount of circuitry as the
original 8088. The redesign of the 8088 has given it greater speed and
increased overall efficiency. One of the V-20's main advantages is that
it runs much cooler than its predecessor, the 8088, which can become
quite hot (a main cause of breakdown) under normal operation. All
programs which will operate with the 8088 will run with the V-20. For a
detailed discussion, see the article in PC Magazine, Vol. 4 No. 26,
December 24, 1985, page 181. The price of a V-20 chip is generally
under $20 and the chip is easy to install yourself. If you have a
regular 4.77 MHz mother board you'll want a 5 MHz V-20, and if your
system uses a turbo board, you should ask for an 8MHz V-20. 8087 Math

The 8087 math coprocessor can significantly speed up (up to 20 times)
the processing of large, time-consuming mathematical calculations.
Software, however, must be specifically written to use it. The latest
version of Lotus 123 is designed to work with the 8087.

The Different Mother Boards

256K Mother Board
The 256K mother boards represent the first generation of XT clone mother
boards and are what IBM initially used on its XT. Even if you come
across one of these boards being sold at a bargain price, avoid it.
You'll save money in the long run to get a 640K mother board. The main
drawback of the 256K board is that only 256K of Random Access Memory

(RAM) can be placed directly on it.

640K Mother Board
This board offers low price with high efficiency. These have become the
dominant and most common mother boards for XT clones. At the present
time this mother board or the 640K Turbo board is what I recommend. The
640K of RAM is installed in 2 rows of 256K chips and two rows of 64K
chips. Being able to place 640K on the mother board is desirable
because (1) fewer chips are needed, making the memory more compact,
cooler-running and more reliable, and (2) no add-on memory card is used,
saving the expense of a card and a memory slot. Turbo Boards

New mother boards are now available with faster speeds than the usual
4.77 MHz mother boards (the clock speed of the computer is measured in
megahertz or MHz). These turbo boards are becoming popular now because
their price has fallen to where they are only slightly more expensive
than regular 4.77 MHz boards. Speeds for turbo boards are typically 6,
7.5 and 8 MHz. If you purchase a turbo board, it's best to look for the
8 MHz model which is the most common and the fastest. The 8 MHz speeds
up the system by as much as 60 percent; however, this speed increase
comes only from the speedup of internal calculations. This means the
greatest benefit comes in running programs such as spreadsheets. There
is not a great speed increase with word processing programs, for
example; the speed at which these programs run is determined more by the
speed of access of the disk drive heads, reading and writing. Turbo
boards can be switched between 4.77 MHz and their faster speed either
with software or hardware. Some programs---primarily graphics---do not
operate at the higher speeds. There are still a few problems with
different turbo boards; some have a tendency to lock up while in turbo
mode. Before buying a turbo board, test it out with several programs to
see how it operates.

4-Layer Mother Board
The four layer mother board's circuitry is better insulated than that on
a standard 2-layer mother board. Two layer boards have all their
circuits in one layer, while the 4 layer boards have a layer of
circuitry, then a layer of insulating material, then another layer of
circuitry, and so on. This has as its major benefit reduced electronic
noise between circuits, which could cause parity errors. This type of
mother board may be advisable for someone with high volumes of data to
process at a low error tolerance level. The main difficulty with this
sort of board is that, if it should crack, it is virtually impossible to
repair. For an average user the added expense of this board and its
potential high replacement cost don't justify it.

Super Mother Board
The super mother board has the floppy disk controller, one parallel and
two serial ports and a clock/calendar all directly on the mother board.
At the present time, it is cheaper to purchase a 640K mother board with
a multi I/O (Input/Output) card, which contains the added features, than
to buy a super board. This is probably due to the large quantities of
640K boards being manufactured; if the super boards start selling in
greater quantities their prices may fall. AT Motherboard

A motherboard is now available that will allow you to upgrade your XT to

an AT. This price of this XT-sized (smaller than AT standard) board is
still high, though. Keep them in mind for future expansion.

Information System, 431 Ashbury St. SF, CA. 94117 (11.95 postpaid)


Flip-Top Case

A very innovative feature characteristic of XT clones is the flip-up
case. This feature above all else helps to demystify the insides of the
computer box for most people. With the flip-up case it's only a matter
of pressing two buttons on the sides of the case and lifting the lid to
expose the interior of the computer. Most people's first response when
they see what's inside is, "Is that all there is to a computer?" Then
they start wondering what they're paying the high price for. The only
other computer I know of on the market that has this easy access feature
is the Apple IIe. Not all XT clones have this flip-up case, but I
highly recommend it against the kind of cabinet which must be unscrewed
for removal. One problem with a flip-top case might be that if the
computer is in a public area it would be easy for someone to open the
lid and quickly help himself to your expansion cards. It's also not the
kind of feature someone who has small children might want. There is a
market waiting for someone to develop a flip-top lock for such

Another potential problem is that the flip-top case may not meet all FCC
requirements. It therefore may no longer be sold, with the slide-out
case eventually becoming standard.

Slide-Out Case
It's very time-consuming to unscrew and slide off the case every time
you want to change expansion cards. IBM uses this kind of case, and it
is available for XT clones. It has the advantage of being a bit
sturdier than the flip-up style, at a slightly higher cost.

AT Look-Alike Case
Some of the newer XT cases have a key lock and indicator lights for
power and hard disk on the front panel, as does the IBM AT. Be careful
when buying this kind of case because some are manufactured with bogus
lights and locks. A drawback of this style is that two drive slots are
inaccessible from the front (as with the IBM AT), and it is therefore
not possible to add a third floppy drive.


When buying a power supply (or shopping for a computer and comparing
power supplies), check for the following features:

1. Minimum 135 watts, so as to have enough power for future expansion.
The new standard for power supplies is 155 watts, and the ones I've seen
feature quieter cooling fans than most 135-watt supplies.

2. Low noise level. Be especially critical of the noise the fan makes-
--a noisy fan gets very annoying after a while.

3. Automatic overload shutdown. Check to see if the supply has
"overload protect." If a short circuit or overload develops in the
computer, the power supply will save itself by automatically shutting
off. This may save other components, too.

4. Open circuit shutdown. This feature turns off the power supply if
an open circuit develops in the computer, another component-saving

5. Switchable voltage. If you're planning to travel with your
computer, make sure the power supply can be switched (110/220 volts) to
accommodate foreign mains power standards.


Disk drives can be likened to cassette recorders---the cassette recorder
saves information in a magnetic medium, and so does the disk drive.
There are many sizes and types of disk drives available, but the common
ones for the XT standard are referred to as 5 1/4-inch floppy disk

Five-and-one-quarter-inch drives are divided into Full Height, Half
Height and Third Height sizes. Full height drives are outdated but IBM
still uses them. The Half-height drives are superior to full height
drives because (1) they consume less power, thereby creating less heat
inside the computer and leaving more power for other uses; (2) they only
take up half as much room (two fit in the space of one full height
drive), (3) their technology is less failure-prone and (4) they operate
more quietly than full height drives. You'd think, if half-height
drives are better than full height, then third-height drives must be
better still, but this does not seem to be the case at present. I've
heard many bad stories about the reliability and noise of third-height
drives, so I would avoid them for now.

Under the half-height, 5 1/4-inch drive classification, there are still
further subclassifications which refer to the disk drives' information
storage capabilities. In order of increasing storage space, there are
single sided, single density (SS/SD), single sided double density
(SS/DD), double sided single density (DS/SD) and double sided double
density (DS/DD) drives. Only that double sided, double density 5 1/4-
inch drives should be used. Buying the cheaper but lower-capacity
drives is short sighted (I'm not sure they're even made any more), there
are many programs which need the DS/DD drive's 360K of memory, and with
lower capacity drives you'll find yourself continuously swapping disks
as they get full.

The next generation of disk drives are the 3 1/2-inch high density
drives, such as the one used on the Apple MacIntosh and several of the
new lap-top portable computers. These drives work with the newly
released PC-DOS 3.2 operating system, and IBM is promoting these drives

and encouraging software manufacturers to make their programs available
on 3 1/2-inch floppies. The 3 1/2 inch drives are still more expensive
than 5 1/4 inch, but when the price drops they should become quite

If you are low on money, you can buy your XT clone with only one drive
at first and add another drive later. However, a computer with only one
drive is inconvenient and cumbersome to use, and many programs require
the use of two drives at once. Also, even if you are planning to use a
hard disk, it's advisable to have two floppy drives with it, for the
added ease of copying from one floppy to the other.

When purchasing floppy disk drives, check for the following:

1. Direct drive, not belt drive operation for better reliability and
less noise.

2. Low noise while reading and writing to the disk. Check this by
copying a program from one drive to the next and running programs.

3. Make sure the drive's manufacturers are still in business.

4. Some drives may be used on both the XT and the AT. Others can't.
If you ever want to upgrade your system to AT standard, you'll want a
pair of AT compatible drives in your XT clone. Some good name-brand
drives are made by Fujitsu, TEAC and Toshiba.

A note about buying floppy disks: there are many floppy disks available.
I have been using generic "no-name" floppies and have found them to be
quite reliable. They can be had for well under 75 cents apiece and seem
to work as well as the more expensive ones.

Information System, 431 Ashbury St. SF, CA. 94117 (11.95 postpaid)


Every accessory (i.e., floppy disk drives, hard disk, monitor, etc.) to
the mother board needs an interface card, also referred to as "card,"
"plug-in board," "expansion board," or just "board." The interface card
controls the operation of that attachment. For the floppy drives, the
interface is a card called a floppy disk controller. The floppy
controller typically can be had as a separate card. Most floppy
controller cards can drive up to four floppy drives, but hardly anyone
uses more than two floppies so this feature is unimportant. When buying
the card, remember to purchase the cable which is needed to connect the
drives to the floppy controller. Use the same criteria for quality as
with the mother board.

If you will need a serial I/O port for a modem or a mouse, a parallel
port for your printer, a game port for a joy stick and/or a battery-
backed-up clock and calendar, you should have a Multi I/O card. This

card has all these features plus a floppy controller, all on one card.
Its price is not high when you consider all the extra features you are
getting. This single card also saves a couple of expansion slots which
you can use in the future.


The interface card for the monitor is referred to as a display or video
card. One of the most difficult decisions for the average computer
buyer is whether to use a high resolution monitor and accompanying high
resolution display card or a color monitor and a color graphics display
card. Base this decision on what your primary use for the computer will

Color Graphics Card

If the computer is primarily for the home and for children, it is best
to use a high resolution color monitor and color graphics card. The
color graphics card is what the IBM computer typically comes equipped
with. This card will drive three types of monitors: (1) monochrome
composite, (2) color composite and (3) RGB (Red/Green/Blue). Clone
manufacturers have made copies of IBM's color graphics card which are
significantly less expensive than the original.

High Resolution Display Card

If the primary use of the computer will be word processing or business,
it is almost a necessity to use a high resolution monitor and high
resolution display card. This is because the text display of a non-high
resolution monitor will quickly tire the eyes. Hercules (a U.S.
manufacturer) set the high resolution standard with its high resolution
graphics card. Taiwanese clone manufacturers have made Hercules copies
which can be had for under $100. The original Hercules card still costs
over $300. Parts for these display cards are all off-the-shelf, and
Hercules only has a copyright on its manual and software which are
needed to configure the computer. Hercules has been fighting an uphill
battle against the clone makers. Early clones, made for use with
Hercules software, were obviously illegal copies, right down to their
photocopied Hercules manuals. The new clone cards improve on Hercules
by placing the configuration software on a ROM chip, thereby eliminating
the inconvenience of loading it from disk. They have also rewritten the
configuration code and, incidentally, have stopped using Hercules'
manual, but only after Hercules had taken several clone dealers to

The advantage of a high resolution monitor and display card is its
exceptionally fine resolution, as of text characters. The
disadvantages: (1) it's monochrome and (2) most graphics game programs
are written only for the color graphics card.

Enhanced Graphics Adapter (EGA)

A possible solution to the choice between high resolution and color is
the Enhanced Graphics Adapter which is now developing as the next

standard. This card allows for both high resolution color and
monochrome, although resolution is still not quite as good as with the
Hercules and its clones. Main problems for now are that EGAs are very
expensive, they need a special EGA monitor which is also costly, and
software needs to be written to take advantage of EGA's features---not
much is yet available. When these problems are worked out, EGA will
become an attractive option.


As mentioned in the previous section on display cards, a color graphics
card may be used with three kinds of monitors. They are:

1. Monochrome composite. This monitor's resolution is poor. It is not
recommended for any use.

2. Color composite. Again, poor resolution makes it ill advised to use
this type of monitor, especially if you value your eyesight.

3. RGB (Red/Green/Blue) high resolution monitor. Anyone needing a
color monitor should opt for this type. Its images are of much better
quality than the composites, above. However, as noted, the resolution
of text is not acceptable for long-term viewing. For word processing,
spread sheets and data base management programs, you'll want a high
resolution monochrome monitor. These monitors are referred to as TTL
(Transistor/Transistor Logic) monitors.

Some features to look for in TTL monitors are:

1. Amber rather than green phosphor screen. The green screen leaves
distracting ghost images behind when the display changes.

2. A tilt/swivel stand (built into the case) is handy for adjusting the
monitor to a comfortable viewing angle.

3. Anti-glare netting across the screen cuts down reflections and
increases contrast. Before choosing any monitor it's a good idea to look
at several kinds to get an idea of their different features.


Personal taste plays a large part in choosing a keyboard. Some people
like keys with a firm feel, some prefer mushy keys, some like a little
tactile feedback while others prefer none.

There are several features which are considered desirable in a keyboard,
although your tastes may differ: 1. IBM Selectric typewriter layout. 2.
Large keys with English labels. 3. LED indicators on "CAPS," "Number
Lock" and "Scroll Lock" keys. 4. Long cord. 5. Raised bumps or
deep-dish caps on the "F," "J" and numeric "5" keys, to help orient

Most keyboard manufacturers have duplicated the IBM PC and XT keyboard

layouts. The keyboard of the IBM AT has many improved features and
there are some keyboards available for XT clones that copy the AT
layout. Some are also switchable for use on either the XT or AT
standard. All else being equal, the new switchable models are the ones
to buy. This is because if you upgrade your XT clone to an AT later,
you won't have to buy and get used to a new keyboard. XT and AT
keyboards are not normally interchangeable. Look on the back of the
keyboard for a little switch; if you see one, it's probably an XT/AT
switchable keyboard. One of these is made in the U.S. by the Maxi-
Switch Company of Minneapolis. Switchable keyboards from Taiwan are
also available.

Anyone who works with spreadsheet programs will find a keyboard like
Keytronics' 5151 (or clones) useful. This model features separate pads
for cursor (arrow) keys and numeric keypad, which are normally combined.
Having the two pads separate is a must for anyone doing heavy number
entry and accounting work because it eliminates having to switch the
Number Lock on and off when moving from cell to cell, and cuts down on
keying errors. HARD DRIVES

A hard disk drive is an enormous convenience, one which allows for large
amounts of easily accessible storage and which eliminates the need to
frequently change floppy disks. For example, if you are doing word
processing you may have one floppy which holds the word processing
program, another for a spelling checker program, another which holds a
thesaurus and still another on which to record your data. To switch
from the word processor to the spelling checker and then the thesaurus,
then save your corrections and go on to edit another data file, you may
have to swap four disks, some possibly more than once. With a hard disk
every function is directly accessible and your flow of work or
creativity need not be broken with housekeeping chores. Also, as
programs become increasingly sophisticated and memory-hungry, the
convenience and capacity of a hard disk become more desirable. Some
programs can't run at all on floppies unless you change from one disk to
another frequently---they take more room than is available on one 360K

Hard disks come in a variety of sizes, just like floppy disk drives.
Presently the half-height, 5 1/4-inch, 20 megabyte (MB) hard disk, which
holds the information equivalent of over 50 DS/DD floppies, is the
standard. The price difference between 10 and 20MB drives is fairly
small so, dollar-for-dollar, it's better to get a 20MB hard disk. Avoid
the bulkier full height hard disks which take up two half-height drive
slots. At present, the best known name in 20 megabyte hard drives is

Another hard disk option is the new 3 1/2-inch hard disks. They are more
compact, use latest technology, draw less power and claim greater
reliability than 5 1/4 inch hard drives. They are also more expensive,
but prices are falling rapidly and should soon catch up with the 5 1/4
inch hard drives and thereby supersede them as a standard.

The new "hard cards" (a hard disk on an expansion card) are basically a
3 1/2-inch hard disk mounted together with the hard disk controller.
This card fits into one of the expansion slots of the computer. This

option could be useful where all four drive slots of the computer are
already in use.


The hard disk controller controls the operation of the hard disk. The
newest controllers use surface mount technology which has greater
reliability and condenses several of the previously used chips into one.
This reduces the size from a full length card to half length. Some of
the well known controllers are from DTC, Western Digital and Omti. To
date, the Omti uses the most surface mounted chips and is the most
compact of the three.

Information System, 431 Ashbury St. SF, CA. 94117 (11.95 postpaid)


The following instructions are intended to guide you in the assembly of
your own IBM XT clone computer. No special expertise is required and
the whole process should take no more than two hours. Important! Read
this guide carefully before you begin assembly. There are a variety of
different cases, screws, drives, etc. available, each with slight
variations in hardware, shape, size, location of mounting points, etc.
This is a general guide for the assembly of an XT clone. Your specific
hardware may be a little different. Use common sense and you will have
no problems putting everything together right the first time.

1. Typical Tools List:
A. (1) Socket and driver (usually 6mm or 7/32 inch)
B. (1) Phillips screw driver (maximum 4" long)
C. (1) Slot (normal) screw driver (maximum 4" long)

2. Typical Parts List (Check to be sure you have everything here
before beginning assembly):

A. Case (preferably flip-top) and hardware:
(3) disk drive slot covers
(5 or so) plastic expansion card support brackets
(4) large screws for mounting the power supply
(10 or so) small flat screws for card support brackets and
(9) brass standoffs
(9) nuts for brass standoffs
(9) screws for brass standoffs
(18) insulating washers
(8) metal expansion card slot covers
(8) screws for expansion cards and slot covers
(1) larger metal plate for securing the drives
(4) rubber feet pads

Hardware for case.

B. Speaker
C. 150 watt power supply
D. Floppy drive(s)
E. Keyboard
F. Mother board
G. Disk controller card with cable. Display card
I. Monitor
J. Accessories: multifunction card, modem, hard disk, hard disk
controller, etc.

A. Check Parts.
1. Open all the packages of parts and make sure everything looks OK.
The solder on boards should look cleanly flowed and there should be no
obvious broken wires, etc. Open the package with the screws. I like to
arrange each of the same sized parts into its own pile before I start.

B. Secure the speaker and card support brackets.
1. Glue or place the speaker over the speaker opening, usually located
under the drive rack on the bottom of the case. If the wires are too
short, glue the speaker in the space behind the front card support cage.
2. Screw the plastic card support brackets to the back of the front
card support cage. (These brackets are used to help support long
expansion cards.)
3. Place the 4 rubber feet on the underside of the case. It may be
necessary to use a bit of glue to make sure they stick properly.

C. Prepare the mother board.
1. Insert any memory chips with the half-moon orientation circles
facing the same way as other previously-installed chips. The memory
chips should all be facing the same way on the mother board.
2. If the BIOS (Basic Input/Output System) chip has not been installed
yet, install it now.
3. Check all pins on the chips to make sure they're firmly into their
sockets, and not bent or folded under the chips.
4. Set the DIP switches according to the manufacturer's instructions.
The DIP switch settings should be in the manual that came with the
mother board.

Typical DIP switch settings:
Switch # 1 (Normally off) 2 ON = without 8087 co-processor; OFF = with
8087 installed. Memory Switch (3 and 4) settings: 3 OFF; 4 ON = 128K
memory installed 3 ON; 4 OFF = 192K memory installed 3 OFF; 4 OFF = 256K
memory installed Display adapter switch (5 and 6) settings: 5 ON; 6 ON =
No display adapter 5 OFF; 6 ON = Color graphics (40 x 20 mode) 5 ON; 6
OFF = Color graphics (80 x 25 mode) 5 OFF; 6 OFF = Monochrome display
adapter or Both Display drive switch (7 and 8) settings: 7 ON; 8 ON = 1
drive installed 7 OFF; 8 ON = 2 drives installed 7 ON; 8 OFF = 3 drives
installed OFF; 8 OFF = 4 drives installed

5. You will want to place the mother board into the case without taking
off the rack that holds the drives. It will be impossible to get to the
screw and brass standoff under the rack later, so put them on first. To
do this, place a fiber insulating washer over the threads of the brass

standoff and insert it through the back hole of the mother board. Place
another insulating washer on top and firmly tighten a nut down onto it.

D. Installing mother board into the case. Use the proper screws and,
from the bottom of the case, attach the remaining 8 brass standoffs to
the case with their threads facing up. Leave the standoffs somewhat
loose now so you'll have some play in them to line them up with the
holes in the mother board. 2. Place a fiber insulating washer on each
brass standoff. 3. Slide the mother board into place, with the 8
expansion slots facing the back. To get it to go under the drive holder
rack, pull up on the edge of the rack to gain enough room for the mother
board to slide under. 4. Line up the standoff threads with the holes.
This may take a little gentle jiggling of the mother board. 5. Place an
insulating washer on each brass standoff and tighten with the proper
nuts. You may have to use a screw driver to keep the screws on the
bottom of the case from turning. 6. Screw in the last screw from the

E. Securing the floppy drives.
1. Make sure the jumpers on the drives are set properly and remove
terminating resistors as necessary. This can be a confusing step if you
don't have instructions for the proper jumper settings. Each drive
model can have a different setting so be sure to find out from the place
of purchase exactly what the proper settings are.

2. The drives can be arranged in the racks as you wish: both on the
left side, both on the right side, or both across the bottom.

It's easiest to place both on the left side (facing the front of the
computer). Just slide the drives in from the front and secure them with
the proper screws. The metal plate is used to secure the other side of
the drives. Secure the bottom of the drives through the holes in the
bottom of the case. A trick to use: put some glue on the tip of your
screw driver during this step. Otherwise it's hard to get screws into
place without dropping them.

F. Install power supply.
1. Mount the power supply to the back of the case and secure with the
four large screws.
2. Connect power cable to pins on the mother board. The correct pins
are the ones nearest the power supply. Normally the power cable only
connects one way. The red wires will face the backs of the drives.
Connect power cables to the drives. Again, they should only connect one
G. Install disk controller.
1. Expansion cards can be plugged into any of the 8 slots on the mother
board; the computer will know where they are.
2. For efficiency, plug the disk controller into the second slot from
the power supply. To get it to go into the slot, use a firm back-and-
forth rocking motion.
3. Connect the cable with the colored line to the number one pin on the
disk controller and drives.
H. Install monitor display interface card.
1. Plug display card into the mother board. Screw it down and make
sure that the bottom is not touching the chips on the mother board.

I. Finishing up.
1. Screw the metal expansion card slot covers to the back of the case.
2. Plug the speaker into its pins on the mother board.
3. Plug in the monitor power cable and the connector to the back of the
display card.
4. Connect the keyboard to the back of the computer.
5. Plug the power cable into the power supply and wall outlet.

J. Test computer.
1. Insert system disk in Drive A and turn the power on. There will
usually be a memory check (depending on the particular BIOS). After the
memory check, you should see a prompt for time/date.

K. Problems...?
If the system does not work properly right away, go back and check that
(a) you performed all steps and (b) all steps were completed correctly.
Pay particular attention to the DIP switch settings on the mother board,
the settings on the disk drives and the connections of all cables. Also
make sure that no RAM or other chips are installed backward or
incorrectly, and that no chip pins are bent.

Information System, 431 Ashbury St. SF, CA. 94117 (11.95 postpaid)


This section is an annotated bibliography of articles written about the
XT clones. If you are aware of published articles not listed here,
please send them to me for inclusion in updated guides. My address is
on the front page of the guide.

Dvorak, John C., "Asian, European Computers at Bargain Prices," San
Francisco Chronicle, Sunday, September 8, 1985, p. D-3. The decline of
computer hardware prices at the Third Personal Computer Faire in San
Francisco is noted. The Apricot F-1 and XT clones are given as

Dvorak, John C., "What's Hot, What's Shot in Business Computers," $San
Francisco Chronicle, Sunday, March 2, 1986, p. D-3.This newspaper
article takes a short look at the state of the market for business
microcomputers. Its main points are:
1. The IBM PC is outdated.
2. IBM XT is current "hot" seller.
3. PC clones make up 50% of computers sold (compatibles and
clones are lumped together as PC clones).

4. IBM AT and clones are future hot sellers.
5. Apple is still around, and popular in the schools.
6. For the MacIntosh to be popular, it needs to move to open
7. The overall trend is toward cheaper hardware prices.

Gelman, Eric, "Soul of a Cheap Machine," Newsweek,
May 19, 1986, pp. 54--55.
This article outlines recent trends in the microcomputer market: rapid
emergence of XT clones and compatibles, and IBM's slipping market share.
Some interesting statistics: 1) XT clones have grown in sales 92 percent
over 1985 and now claim a 25 percent share of the PC/XT standard market
for microcomputers; 2) the compatibles' share has grown 36 percent for
the same period to a 30 percent share of the market; and 3) IBM has had
a 31 percent negative growth and slipped from 65 to 45 percent of the

Kanter, Elliot S., "Part 1: PC Compatible Computer,"
Radio-Electronics, July 1985, pp. 43--82.
This article is Part One of two parts which describe the Hiteck XT clone
and how to assemble it. In this section, the author states that
building your own clone is cheaper than buying an IBM; it's easy, and
the parts are interchangeable with IBM. He then gives a good background
history of the IBM PC/XT's development and position in the computer

Kanter, Elliot S., "Part 2: PC Compatible Computer,"
Radio-Electronics, August 1985, pp. 67--71.
This article continues from above. The focus here is on the actual
assembly of the Hiteck PC compatible (clone) computer. DIP switch
settings, jumper settings, installation of hard disk and controller are
all covered. There are many useful pictures of the various component

Kleiner, Art, "A Home Computer Shopping Guide," Bay Area
Guardian, November 27, 1985, pp. 25--28.
This article gives general advice on buying a computer. It begins by
reviewing the Amiga, Atari ST and the MacIntosh. These machines'
excellent graphics and use of icons are highly praised.

Their drawbacks of limited software and small user base are also noted.
The article states that the IBM standard has almost a complete monopoly
on the best business software, such as accounting, time management and
word processing. The generic clones are recommended because they run
most of the software you'll need. Many of the parts are the same as
IBM, and they're cheaper. The drawback of minimal support is noted.
The buyer is warned to avoid CP/M and the PC Jr. completely because
there is a lack of software for these computers.

Pilgrim, Aubrey, "You Can Build a PC-XT, For Half The Cost,"

MicroTimes, September 1985, pp. 48--50.
This article relates how one person assembled his own XT clone for "half
the cost" of an IBM XT. The author had a Morrow (a CP/M machine) and
wanted to expand up to an IBM, but the cost was too high. He became
sold on the clones because the cost was low and the compatibility with
IBM was high. He then bought the parts and assembled his own system.
There is a list of suppliers given for the San Francisco Bay Area.

Pilgrim, Aubrey, "Add-Ons For The Do-It-Yourself PC-XT,"
MicroTimes, January 1986, pp. 72--76.
The main point made in this article is that XT clones have surpassed IBM
in almost every respect. The main reason is that the clone
manufacturers are small companies which can rapidly change and innovate.
Examples of improvements over IBM are given for the keyboard, floppy
disks, mother board, hard drive, etc. A list of 55 suppliers, mainly in
California, is given.

Raleigh, Lisa, "No-Name Brands: Buying Garage Built or Mail
Order Computers Can Be Cheaper or Costly," San Jose Mercury
News, Sunday, October 20, 1985, pp. 16F--18F.
This article discusses the "no-name clones." It begins by saying the
clones are significantly lower in price than IBM, and discusses the
negative and positive points in buying a clone.

Negative points:
1. Some people say there are lots of bad clones out there.
2. There is bad manufacturing.
3. Suppliers often go out of business.
4. The buyer takes a chance on reliability.
Positive points:
1. One takes a chance with any computer.
2. Clones are inexpensive.

Keep in mind while shopping for a clone:
1. Read ads carefully and ask lots of questions.
2. Test for IBM compatibility.
3. Look for a supplier you can work with.
4. Ask for references.

Seymour, Jim, "'The Corporate Micro;' 'Generic' PC Gap a Matter
Of Price, Not Excellence,"PC Week, August 13,
1985, p. 21
The author notes that inexpensive clones are starting to hit the market.
He has tested a clone and found it to be faster than an original IBM XT.
They are fine machines, he concludes, and he would buy one instead of an
IBM. The buyers will probably be either persons with an IBM at work who
want a compatible at home or small businesses. Corporate buyers
probably won't buy the clones because they want the IBM status. The
author thinks. however, that price should be more important and that
corporate buyers are making a mistake.

Welch, Mark J., "Interest Grows in Generic Computers,"

InfoWorld, January 27, 1986, pp. 24--27.
According to the article, large companies are beginning to show interest
in XT clones. The clones have some advantages such as low price, small
dealers who give personalized and faster service than IBM, and the
compatibility and reliability of the clones is good. Some purchasing
agents require the IBM logo, however; "it's the warm, fuzzy blanket they
need." It's estimated that only one-half of 1 percent of the computers
in business use are XT clones. The article also notes other general
information about XT clones and use in companies.

Rosch, Winn L., "Cost Conscious Computing," PC
Magazine, October 15, 1985, pp. 113--120.
This article analyzes some PC compatibles according to their price and
capabilities. Computers covered are: Leading Edge Model D, Morrow Pivot
II, Tandy 1200 HD, Tandy 1000, PC Designs FD-1000 and the IBM Portable.
It says the PC Designs (clone) is: 1. Easy to assemble. 2.
Faster than the IBM PC because of its 8 MHz clock speed. 3. A top-
performance bargain, if you're up to assembling your own computer.

Rosch, Winn L., "PC Designs FD-1000: From Kit to Computer in
Two Hours or Less," PC Magazine, October 15, 1985, p. 117
This article states that it is not difficult to assemble an XT clone
kit. It details the assembly of an XT clone sold by PC Designs called
the FD-1000.

Viet, Stan, "Curing PC Clone Confusion," Computer
Shopper, March 1986, pp. 6--10.
A lot of good background information is given in this article. It
covers (1) IBM, (2) the IBM "grey market," (3) the MS-DOS IBM
compatibles and (4) some things to look for when buying a clone, and why
to get them. Minimum things to ask for: 1. 640K. 2. Large
power supply---135 watts plus. 3. Two floppies. 4. Good video
display. 5. Good monitor. The differences between IBM
compatibles and clones are not clearly explained.

Information System, 431 Ashbury St. SF, CA. 94117 (11.95 postpaid)


The following are discussions about XT clones taken from the IBM XT
Clone User Group of San Francisco computer Bulletin Board Service (BBS).

If you have comments, feel free to call the BBS. The number is listed in
the Introduction at the beginning of this guide.

From: Brian
To: All
Subj.: Are compatibles worth it?
I'm thinking of getting an XT compatible, but I can think of
several very good reasons not to:
1. Technical documentation: I'm just learning assembly language,
so I figure I will need to know technical details about ROM-BIOS,
busses, chips, and who knows what else. Is that kind of
information available for a compatible?
2. Repairs: Who repairs no-name machines with parts made by a
variety of companies?
3. Resale value: I have an IBM PC, and I expect to be able to
recover a large percentage of its cost when I sell it second
hand. I assume, though, that no one buys second-hand no-name
compatibles unless they can find a very good deal on
them. Any responses?
P.S.---If you do decide to get a compatible, how can you
tell the good ones from the bad ones? They all promise about the
same features.

From: Alan
To: BrianSubj.: Buying an XT compatible
You're right about the reasons for shying away from an XT
compatible. I don't remember whether you mentioned
compatibility; I haven't seen any machines that are 100%
compatible. One option you might consider is upgrading your PC
to a PC XT. You probably know that the only differences between
the two are that (1) the XT has a 135 watt power supply instead
of a 95 watt (60 watt) supply, and (2) the XT has some extra
slots. I have seen stronger power supplies on the market, so you
might consider just getting a new supply, and then buying a good
quality hard disk.
When I bought my machine, I decided to go with the IBM XT.
The best way that I've found for making these kinds of decisions
is to read the reviews in magazines. For example,
InfoWorld recently did a review of the Leading Edge Model
D. Also, I think they had an article on no-name compatibles
lately. They concluded: buy one only if you can save at least
50% off the cost of the machine it imitates.

From: Brian
To: Alan

Subj.: Compatibles
Thanks for the response on compatibles. The problem with
updating a PC is that it costs more. I could probably sell my PC
for $1400 or $1500. For two or three hundred more than that, I
could buy most of the available clones---including 20MB hard
disk, 640K, clock, mono graphics, two drives, and maybe even dual
speeds. To update the system it would have cost $130 for a 384K
card, $90 for the power supply, and at least $450 (probably more)
for the hard disk---that's a conservative $670, or about $400
more than the clone. I don't have that much money right now.
Maybe a name brand compatible, such as Leading Edge, would be a
good compromise---not IBM, but a known company to support it and
a recognizable name that might actually have some resale value
when I outgrow it. IBM would certainly be the safest thing,
though. And thanks for the advice about reviews---I'll start
checking InfoWorld.

From: Alan
To: Brian
Subj.: Buying a compatible
I see your point concerning the price of upgrading your PC.
I talked with someone at the San Francisco PC users group who
liked his Leading Edge and the people he bought it from.

From: Edwin
To: Brian
Subj.: XT clones I think the XT clones are the best computers
on the market
at the present time considering the price and performance.
Specifically to respond to your questions:
1. About technical information: The only difference between an
IBM and a clone is the BIOS. The BIOS on the clones are
generally quite close to IBM's. In fact, if you could get an IBM
BIOS and put it into a clone, you would have an IBM XT. Almost
all programs I've tried have worked on the XT clones. You could
probably write a program using IBM's specifications. This area
needs more research, though.
2. About repairs: The clones are very easy to repair, the parts
are standardized and any computer repair place should be able to
fix them. Also, you can easily repair them yourself by swapping
parts to determine which is defective.
3. About resale: I think the resale for clones should be good.
I suspect it would be better than the compatibles, by such I mean
Leading Edge, Kaypro, etc. (the computers that are not completely
hardware interchangeable with the IBM XT).
4. The qualities for the XT clones are also quite good.
Typically if you don't have any problems with it during the
warranty period, you won't have problems with it later down the
If you want more information on the clones, leave a question
here or come to the next meeting of the IBM XT Clone User Group.


From: Allen
To: Brian
Subj.: Clones
You have brought up some good points.
The IBM tech manual should tell you most of the information
you would want to know about a clone. As to be compatible, it
must use the same memory and I/O port addresses. You could ask
the seller if he could get you a listing of the ROM-BIOS. This
could have more or less the information that the Tech. manual has
in it. And should be cheaper. $40 for that tech manual. Most
sellers of Clones make or at least test their own systems and
have people who can fix them. You should ask them about this and
talk to their Tech people.
You can get a clone that will run at 8 mhz. This can help a
lot when assembling. As it can get slow when you need to change
one line of code and the reassy.
As for resale value, the prices are always going down so I
would not put much hope in getting a good price even on an IBM.
Get a machine that you can use for a long time.
Also, think about getting 20Meg disk and think about all of
the other things you'll need as the resale price on old parts is
real low.

From: Edwin TO: All
Subj.: clones
Concerning the clones with the 8mhz turbo boards. If
someone is doing professional programming, it may be an idea to
get an AT clone. The speed is much faster than the XT clones
even with a turbo board. The cost, however, is at least double
that of the XT clone.

From: Dave
To: Brian
Subj.: Do It
Brian. I have a clone with no name, and like it a lot,
works the same as a pc in every respect i have been able to test
(including interrupts) and the price was easily 1/3 of ibms.
I want to repeat a quote I heard that pushed me towards
clones, esp. cheapies..."If you're going to buy one now, get the
cheapest configuration you can find, because it will be obsolete
within 3 years." Of course, I don't necessarily agree that the
computing power of a 640k MS DOS machine will be worthless in 3
years, but it sure is possible, and if you are going to be
looking at your pc with the same sad eyes as osborne users have
when they look at their machines, you might as well have cut your
When they say you're paying for the letters (and only 3 of

them at that), it's true. don't be a sucker.

From: Jeff
To: Brian
Subj.: Clones
Brian, for whatever it's worth, I found myself in exactly
the same position with an IBM PC1---the old 64K motherboard. I
finally sold it and put together a clone. I couldn't be happier.

I use an XT at work, and much prefer the clone. I'm using an XT
turbo board put out by American Research Corp., and an 8 MHz NEC
V-20. If there is a piece of software this thing won't run I
haven't found it. I will say, though, that there are clones with
less compatible BIOS ROMs. I think that in many cases they are
the better known manufacturers (such as Leading Edge) who are
afraid of attracting too much attention from Big Blue. I guess
you take somewhat of a chance repair wise, but with mother boards
going for less than $200, it's almost cheaper to throw the thing
away. The only compromise I've made toward IBM is the keyboard.
I like IBM's and was able to pick one up new for $50.00 from
someone who'd bought a Keytronics.
Whatever---good luck!

Information System, 431 Ashbury St. SF, CA. 94117 (11.95 postpaid)

E BUYER'S GUIDE EDWIN Rutsch Copyright @ Modular
Information Syst

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