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Main => Software Forum => Topic started by: AllanSim on March 02, 2004, 09:44:45 pm

Title: DOS and the 64 meg limit
Post by: AllanSim on March 02, 2004, 09:44:45 pm

DOS can't see over 64 megs, traditionally.  This is what's in config.sys

DEVICE=C:\WINDOWS\HIMEM.SYS /EISA
DEVICE=C:\WINDOWS\SMARTDRV.EXE /DOUBLE_BUFFER
DOS=HIGH,UMB
DEVICE=C:\WINDOWS\EMM386.EXE NOEMS
FILES=30
BUFFERS=20

MEM reports that I have *over* 64 megs, which is good, but MAME acts like there's still a limit there!  Any ideas on if I've done something wrong, or perhaps on an old  memory manager out there?

Title: Re:DOS and the 64 meg limit
Post by: Chris on March 03, 2004, 11:41:12 am

Do you need EMM386.EXE for something other than MAME?  MAME uses DPMI memory from CWSDPMI, so unless you're adding EMM386.EXE for something specific, you may not need it and it may be causing the problem.

DOS's physical limit is at 256MB.  Different versions of HIMEM and EMM386 top out at different levels below this.

--Chris

Title: Re:DOS and the 64 meg limit
Post by: AllanSim on March 03, 2004, 05:24:35 pm

Thanks for your reply.  I'll try removing the EMM386.  The versions of EMM386 and HIMEM.SYS are from Win98.

*DOS's physical limit is at 256MB.  Different versions of HIMEM and EMM386 top out at different levels below this.*

Really?  I didn't know that...everything I read about DOS says 64megs is the limit.  I noticed that MEM said I had only 64megs of RAM until I added the /EISA switch to the

"DEVICE=C:\WINDOWS\HIMEM.SYS /EISA"

line.

**UPDATE**

It seemed to have worked.  Thanks.