ID:WZ Maximizing Window Size in DESQview
Quarterdeck Technical Note #161
by Dan Sallitt
last revision: 13 February 1992
First, the basics: If you have any kind of expanded memory or if you have
extended memory and have placed DESQview's QEXT.SYS driver in your config.sys
file, you should be starting DESQview with DV.COM or XDV.COM instead of
DV.EXE. Most users have a DV.COM file in their DESQview directory, either
because the DESQview Install program placed it there or because of the
recommendation in our documentation that XDV.COM be renamed to DV.COM. In
this case you can simply type DV at the DOS prompt and be assured that the
.COM file is being used. However, some users do not have a copy of DV.COM in
their DESQview directory and start DESQview with the DV.EXE file instead of
the XDV.COM loader. Failure to start DESQview with the .COM file is a
possible reason that window size may fall short of the user's expectations.
If you are starting DESQview with the proper executable file and you still
can't open a window as large as you think you should be able to (our
documentation includes a table that gives you an idea of what to expect),
there are several common reasons.
1) Drivers and terminate-and-stay-resident programs (TSRs) loaded before
DESQview may be taking more memory than you expect.
The amount of memory available to a window inside DESQview decreases as more
memory is used up before DESQview; this is true no matter how much extended or
expanded memory is on the system. If you want to decrease this overhead, you
have a few options.
a) Streamline your CONFIG.SYS and AUTOEXEC.BAT files.
b) Load some programs inside DESQview. If a TSR doesn't
have to run before DESQview (obviously, some programs, like
disk caches and print spoolers, will not serve their
function when loaded inside a window), it's much more
memory-efficient to let DESQview manage it. Even some
CONFIG.SYS drivers can be loaded inside a DESQview window
using DESQview's DEVICE.COM utility.
c) If you have the Quarterdeck Expanded Memory Manager-386
(QEMM-386), or if you have expanded memory that can be
mapped freely in the area between 640K and 1024K and you
have Quarterdeck's QRAM.SYS utility, you may be able to
decrease your memory overhead by loading devices and TSRs
into high memory. (You may even be able to do this if you
have an expanded memory manager with its own high-loading
capabilities, such as All Computers' ALLEMM4.SYS for the All
Chargecard.) Any unused address spaces between 640K and
1024K (different systems will have different amounts of free
space in this area) can be filled with expanded memory and
used to run small programs that would otherwise occupy
It is worth remembering that DESQview loads itself high (with its XDV.COM
driver) in the same areas that QEMM-386 and QRAM use to place drivers and
TSRs. If you place enough programs in high memory before running DESQview,
you will sooner or later reach a point at which the high loading no longer
increases your window sizes inside DESQview, because DESQview will be forced
to start loading pieces of itself in low memory when high memory gets crowded
enough. At this point one can sometimes get creative in finding new places to
put RAM in the reserved memory area between 640K and 1024K. Which brings us
to the second reason that memory figures inside DESQview may be falling short
2) On an extended or expanded memory system, less of DESQview may be going
into reserved memory than is possible. To evaluate this situation properly,
it's helpful to have some experience with DESQview's normal use of reserved
memory. A few rules of thumb apply, however.
a) On 80286 systems that have the first 64K of extended
memory free, DESQview's XDV.COM loader can put 63K of
DESQview code into extended memory if the QEXT.SYS driver is
in the CONFIG.SYS file. On 80386 systems, QEMM-386 obtains
the QEXT effect automatically for you; if you are using
another memory manager, you may wish to tell it to leave
behind 64K of extended memory and use QEXT.SYS. (Compaq's
CEMM is also able to obtain the QEXT effect without QEXT
b) On some expanded memory systems DESQview can put some of
its code in unused video areas. The A000-AFFF area (640K to
704K) is used for EGA and VGA graphics, and should be
available if EGA and VGA graphics aren't used. The
B000-B7FF area (704K to 736K) is used for monochrome text,
and should be available on a color system. The B800-BFFF
area (736K to 768K) is used for color text (and sometimes
for Hercules graphics), and should be available on
monochrome systems. You can try including the appropriate
areas on your memory manager's CONFIG.SYS line.
c) Some expanded memory managers (notably the Intel
Aboveboard Plus) only allow memory mapping to occur
immediately above the expanded memory page frame. See our
technical note on the Aboveboard Plus for information on how
to maximize this mappable area.
d) Adventurous users of QEMM-386 version 5.0 will notice
that the command QEMM ANALYSIS gives a list of the different
areas of memory that may be claimed for DESQview and
QEMM-386's LOADHI function to use. This utility, which
should be acted upon only after it has been run on several
occasions after you have run the full complement of programs
that you normally use, should give you an idea of which
areas in your system ROM may in fact be unused and available
for including with the QEMM-386 INCLUDE parameter. There is
an element of trial and error to this process, but the
rewards can be substantial. Even if you are using another
memory manager or an earlier version of QEMM-386, it may be
possible through a series of blind attempts to find unused
ROM areas that can be included and used to decrease your
memory overhead. The ROM area F000-F7FF, sometimes used
only by the ROM BASIC, is a favorite area to try including;
sometimes a slightly smaller inclusion, such as F200-F7FF,
is necessary. If you guess incorrectly, your machine may
not boot properly, so you may wish to keep a bootable DOS
diskette handy during this process.
3) Sometimes DESQview's Setup program contains excessive memory allocations
that cut down on DESQview's overall memory. The two fields that are abused
most often in this regard are both on the Performance option of the Advanced
"Common Memory" is memory used by DESQview to manage its windows, and the
amount you need is usually proportionate to the number of windows you open.
The default value is 17K; the minimum value of 14K is adequate for users who
open no more than five or six windows at once. Few users need more than 20K
of common memory.
"DOS Buffers for EMS" is memory used by DESQview to manage file operations
into expanded memory. The default value is 2K; users of QEMM-386 who are not
on a network can set this figure to 0K with no loss of performance and a
memory savings of about 5K. The value of this field can affect the speed of
disk access; however, it is rarely worth while to choose a value higher than
10K or 15K.
If you wish to throw away a few DESQview features, you can probably scrimp a
few more K from the Setup program.
On the Keyboard option, you can save as much as 12K if you tell DESQview that
you don't wish to use the Learn feature. This will disable DESQview's very
useful macro system.
On the Video Monitor option, you can save anywhere from 0K to 16K if you tell
DESQview that you don't wish to display text and graphics at the same time.
This will disable DESQview's Video Options menu, prevent graphics programs
from being seen when they are in background, and prevent virtualization of
You can save another 2-9K by choosing 0 for "What Display Adapter do you
have?". This causes DESQview not to load a video driver. This will keep
DESQview from saving and restoring graphics screens or virtualizing graphics.
On the Performance option, you can save 2K by setting the "Manage Printer
Contention?" field to N. (However, this field defaults to N.) This means that
DESQview will not intervene to prevent two programs from printing at the same
On the Network option, you may disable the network support, or decrease the
size of the buffer. This support is needed only for certain network-specific
program, not most normal DOS applications that are merely run off the network.
The amount of memory you will save will be about 5K plus the size of the
buffer reserved in the second field. Unless you know that you need this
service, you should try running without it and seeing if you have problems
without it that you do not have with it. You may also try decreasing the size
of the buffer. The default is 8K.
*This technical note may be copied and distributed freely as long as it*
*is distributed in its entirety and it is not distributed for profit. *
* Copyright (C) 1990-2 by Quarterdeck Office Systems *
************************ E N D O F F I L E *************************