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DOS Memory in Windows 95

Running short of DOS memory after installing Win95?

Your CD-ROM drive does not Work?

You have no Mouse for the DOS Games?

Win95 does not need an autoexec.bat file or a Config.sys file and actually might perform better without at times. Do you need them? You do not if all you are using is Win95 and all your hardware is Win95 capable (have Win95 drivers) and all your software applications runs under Win95. However, some of us still have hardware which does not have protected mode drivers (only real mode) and some of us have games or favorite applications that still likes to run in DOS only mode. In this case we need Config.sys, Autoexec.bat and also a Dosstart.bat file and we need lots of low memory. Some of these games need up to 600K worth of it.

Here are thoughts and ideas for memory management. The basic principle is to minimize what you load and to attempt to load as much as you can high - meaning above 640K - to maximize the memory available for programs below 640K.

Device=C:\windows\himem.sys
Device=C\windows\emm386.exe  noems     (use Ram instead if requiring EMS memory)
DOS= high, umb
lastdrivehigh=Z                 (makes sure the letter is high enough to account for all drives)
Devicehigh=c:\windows\command\ansi.sys         (do not use this unless you need it)
Devicehigh=C:\WINDOWS\SETVER.EXE    (do not include unless you need it)
Devicehigh=C:\CDPRO\VIDE-CDD.SYS /D:MSCD001

The last line loads the CD-ROM driver. Yours will be different. In most cases it does not hurt to load this and it is needed to enable CD-ROM when using DOS. If it does cause problems there are alternatives.

Use buffershigh, fcbshigh,  fileshigh and stackshigh if needed. Do not load a higher number than needed they all take space. Typically, you may need

buffershigh=10

fileshigh=20

If you have legacy devices that do not have protected mode drivers they need to be loaded. The same maybe true for special devices that requires drivers for DOS mode if you intend to use them after going to DOS mode from Win95

Do not load anything you do not need. This file should only contain set statements and path statements. Again you may have to load a real mode application if you have devices not supported by Win95. This is true for some older CD-ROMs.

This file is located in \windows directory. There may not be any such file in which case you need to make it. This file is read when exiting from Win95 to DOS mode whether you do it by selecting Start ---Run--->shutdown to DOS or whether you run a program that requires DOS only mode.

Here you need to load the devices needed in DOS. These could include items such as CD-ROM, Sound, Mouse, Smartdrive and more. Again, do not load items you do not really need. Typically this file might look something like this:

C:\WINDOWS\CTCM                                                          (loads Creative Audio)        
LH C:\WINDOWS\SMARTDRV                                          (loads smartdrive)  
C:\MSINPUT\MOUSE\MOUSE                                            (loads MS mouse)   
LH C:\WINDOWS\COMMAND\MSCDEX.EXE /D:mscd001   (Loads CD-ROM) 
LH C:\Tools_95\GUEST                                                                (loads ZIP drive)

Now, I would not load all of these, just the ones I need. Smartdrive, while certainly speeding up disk access might not be needed. Neither would I load the ZIP drive unless I needed it.

Make the files and let see how we are doing.

Reboot the system and hit F8 when it says "starting win95". Select command prompt from the menu. That will start DOS mode. This will load config.sys and autoexec.bat.

From the command prompt type mem /c/p. It provides a list of items loaded and where they are loaded. There will be two columns " Conventional " and      "Upper memory".  Look at free Conventional Memory. If the number is well above 600K then we are fine so far.

Now boot Win95 and shut down to DOS mode. Repeat above. Again if free conventional memory is well above 600K we are OK if not we need to try something.

First item to try :

If you are not using Doublespace or drivespace (compressed drives) then do the following:

Use Windows Explorer and find MSDOS.SYS. Right click and select properties. Then uncheck hidden and read only.  After all the lines with xxxx's you are likely to have a statement maybe both

drvspace=1

dblspace=1

Set both of these to  0 and then save the file as MSdos.sys. Answer yes to overwrite. Now, Use right click on MSDOS.sys again and check the boxes hidden & read only.

Reboot and check both as above. Again if in both cases you have well over 600K of free conventional memory your fine. If not, you need to see how much free memory you have after accessing DOS from WIN95. Take a careful look at free conventional memory, and free upper memory. Take a survey of the items loaded in lower memory and compare with the free upper memory.  Remember you may have loaded a small file in upper memory and as a result there is just not enough room to load a larger file. In this case you may change the order in which files are loaded or maybe not load the smaller file high to leave room for the larger file.

Memory managers takes care of this for you and maximize the use of memory. Loading items in high memory is kind of tricky since the order is important and since items loaded in high memory normally needs contiguous memory space. Thus you could end up with what appears to be enough free memory but not be able to load something in upper memory.

You can also run memmaker (the DOS 6.2 utility) or any win95 compatible memory manager. It is on the CD-ROM. To do so you need to copy the following files from the CD-ROM\other\oldmsdos

Memmaker.exe ;
memmaker.hlp;
memmaker.inf;
sizer.exe;
and chkstate.sys;

  Memmaker assigns location in hi memory for each item it is trying to load and tries to optimize the places to load each item. The strategy for using memory maker is to add all the stuff you want in autoexec.bat and in dosstart.bat together in one autoexec.bat file. This is the same as what you would want if you booted directly to DOS. Then run memmaker from the start --->run command. After your done move the items you want in Dosstart.bat back including the addresses. Leave all the addresses for the remaining items.

Note: Once you got enough memory you could use the Dosstart.bat as an alternate Autoexec.bat if you are booting directly to DOS.

Key items:

DO NOT LOAD ANYTHING YOU DO NOT REALLY NEED

Minimize the files and buffers - they take space

Do not load setver or ansi.sys unless you really need them. Most of the time all you need is the CD-ROM driver.

Use noems unless the games your running requires EMS in which case you use RAM.

Don't load smartdrv. Most games run fine without. It is a benefit for everything using disk access a lot. You may not need to load the mouse. Actually, often all you need is CD-ROM  

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