The persistance of DOS
by Alan Zisman
(c) 1997. First
published in Computer Player, April 1997
If you believe the hype, Windows 95 can forget about
DOS. Like a lot
of advertising hype it's absolutely true. Part of the time.
Windows 95 does a good job of insulating its users
from 1980s-era DOS
limitations like the 640 kb memory dead-end and work-around memory
schemes. Or from having to fiddle with the Config.sys and Autoexec.bat
startup files. And a lot of the time, it actually works as advertised,
allowing users to simply start up a DOS program, and have it run
that was much less often possible with Windows 3.1)
But while DOS may be buried, it's not quite dead, yet.
efforts to convince us that Windows 95 is the present and future of
development, many game developers are not quite convinced. They've
accustomed to the power they had, under DOS, to directly access the
hardware-squeezing out the best possible performance for their games.
While many popular games are still being written for
DOS, most are running
properly in a Windows 95 DOS session. And that's nice for users-it
that these games can take advantage of Win95's CD-ROM, sound, video,
mouse drivers. In those cases, users don't have to mess with the DOS
But many users want to keep playing their old DOS
games on their new
computers or under their upgraded operating system. Or they just bought
a new copy of a classic game, perhaps re-released at a bargain price.
these golden oldies often won't be so happy sharing the computer with
All is not lost, however. Win 95 allows users
in setting up DOS sessions-far more than Windows 3.1 ever did. (Yes,
fans-not as much as that infinitely flexible operating system permits).
Here are a few tricks that should let you run almost
every DOS program
under Win95 without having to resort to clumsy workarounds like
* Increase the amount of ram in your default DOS
Win95 lets you run a computer without needing the DOS
Config.sys and Autoexec.bat. In doing so, however, it doesn't optimize
your computer's DOS sessions. Find out how much free DOS memory you
by starting up an MS-DOS window, and typing MEM. (Yes, press Enter). If
you have less than 600 kb or so free, some DOS games will refuse to
You can increase the amount of free conventional (DOS)
memory with a
little fussing around with your Config.sys file. Start up Notepad (from
the Start Menu's Programs/Accessories submenu), and open
if you don't find one, make a new file. Make sure it has the following
Save the file, shutdown and restart. Open a DOS
session, type MEM again,
and see how much free memory you've gained. It may still not be
that case, you will have to check deeper into the workings of your DOS
* Are you loading unneeded DOS drivers in Config.sys
If you've upgraded from an older DOS/Windows setup,
you may be loading
unneeded DOS drivers, particularly for your CD-ROM, sound card, and
Open your Config.sys file again-check it for additional lines starting
'Device=' or 'Devicehigh='. These are loading device drivers-software
your system to work with hardware add-ons. In most cases, these are not
needed, as Windows 95 provides drivers for most hardware devices that
use up your precious DOS memory.
If you find such statements (besides the Himem.sys and
previously listed), don't delete the lines. Instead, 'comment them out'
by typing 'Rem' and a space at the front of each line. Save thefile.
open C:\Autoexec.bat in Notepad. Check for lines loading what seem to
Mouse or other hardware drivers. (You can ignore any lines starting
the word 'Set'). Comment them out the same way. Save, and restart your
system. Check and see if your hardware-CD-ROM, sound card, mouse, and
forth are working properly. If so, you don't need those DOS drivers.
don't delete those lines just yet-you're going to need them!
Open a DOS session, and type MEM one more time. At
this point, you should
have at least 605 kb free conventional memory, which should be enough
most DOS programs.
This is a good start, but you may not be done yet. In
next month's column,
we'll look at what to do if your programs insist on EMS (expanded
or need to run in Win95's special MSDOS Mode.