HIMEMX lets you limit RAM. I have no idea if it works with QEMM, though.

You might also have a "memory hole" option in your BIOS that will cut you down to 16 MB.

simbin wrote on 2020-06-30, 05:02:

I'm using QEMM in a new project, but I'm not too familiar with it. I need to limit the XMS for some older games to work, and I only know about EMM386 options. Does anyone know a solution for QEMM?

QEMM includes a utility called "XMS" that allows you to allocate and free XMS blocks from the command line. You can use it to allocate all the extra XMS before running that game.

mkarcher wrote on 2020-06-30, 05:46:

QEMM includes a utility called "XMS" that allows you to allocate and free XMS blocks from the command line. You can use it to allocate all the extra XMS before running that game.

This sounds exactly like what I need, if I can just figure out the right commands. The default help is a little confusing.

I just use XMSDSK that is a ramdrive utility that can be loaded, unloaded, re-configured and also be told to start consuming ram over 16mb so some picky games work fine.
I just load it , consume the extra ram that causes issues and once game is finished I unload it. No special memory managers needed and there are EMS and XMS versions of it.

You can grab it here: https://ftp.sunet.se/mirror/archive/ftp.sunet … /msdos/ramdisk/ , it's the furd19_i.zip file

keropi wrote on 2020-06-30, 06:54:

I just use XMSDSK

Works perfectly, thanks!

simbin wrote on 2020-06-30, 08:47:

keropi wrote on 2020-06-30, 06:54:

I just use XMSDSK

Works perfectly, thanks!

awesome, for xmsdsk be sure to use the /t and /y switches to use ram after 16mb and not get asked 😁

keropi wrote on 2020-06-30, 09:01:

awesome, for xmsdsk be sure to use the /t and /y switches to use ram after 16mb and not get asked 😁

Does this look right?

1xmsdsk 30000 D: /t /y
2game.exe
3xmsdsk 0 D:

simbin wrote on 2020-06-30, 09:04:

Does this look right? […]
Show full quote

keropi wrote on 2020-06-30, 09:01:

awesome, for xmsdsk be sure to use the /t and /y switches to use ram after 16mb and not get asked 😁

Does this look right?

Copy code to clipboard

1xmsdsk 30000 D: /t /y
2game.exe
3xmsdsk 0 D:

yes except the last line, use this to completely remove xmsdsk: XMSDSK /u /y
maybe 0 size works the same too, I just use the unload switch

keropi wrote on 2020-06-30, 09:16:

I just use the unload switch

Very nice, thanks. You wouldn't happen to know a good CPU slowdown utility that can operate similarly?

I use L1 cache disabling utilities, for example ICACHE slows down my 233mmx system to 386DX speeds and works the same as xmsdsk
moslo and similar solutions do not work well enough for my liking, really really old games are OK with them but somewhat newer ones behave weird

what is the cpu of the system you are trying to slow down?

keropi wrote on 2020-06-30, 09:45:

I use L1 cache disabling utilities

what is the cpu of the system you are trying to slow down?

I've had great success with some of those utilities like SetMul in my typical builds. This project is a little unusual, as I'm working with a FPGA core. I'm targeting 286 speeds and got some games working with SLOWINT1, but moving the mouse cursor causes a trail of garbled graphics. I think SLOWDOWN may work, but I'm confused by its command line options.

ah.... no idea then
I am using ICACHE or the system's hardware turbo functions...

EATXMS will do just that--eat up a specified amount of XMS memory, which can be useful for games that won't run on machines with more than 16 MB of RAM.

MAZter wrote on 2020-06-30, 13:27:

EATXMS will do just that--eat up a specified amount of XMS memory, which can be useful for games that won't run on machines with more than 16 MB of RAM.

Yes but you won't be able to recover the ram until you reboot.
XMSDSK has 2 advantages:
- it can be unloaded
- it can be instructed to leave the lower 16mb of ram free so there are no DMA issues with some games

yeah , I spent quite some time to find this nice solution 🤣 🤣 🤣

keropi wrote on 2020-06-30, 13:31:

Yes but you won't be able to recover the ram until you reboot.

Nice, but usually 16Mb is enough for any Dos game. So no any reason to reboot.

simbin wrote on 2020-06-30, 09:30:

Very nice, thanks. You wouldn't happen to know a good CPU slowdown utility that can operate similarly?

Someone just posted about this new thing called CPUSPD the other day.
CpuSpd - A Hardware Based CPU Speed Control Utility for DOS/Win9X Retro Gaming