Monthly ArchiveApril 2002
Tech Guides 24 Apr 2002 06:00:41
Beating WinME’s 512 MB RAM Limit
I have Microsoft Windows Millenium Edition and I have 2 blocks of 512 MB RAM. Until yesterday I had only had 1 512 MB block installed, because of a limit in non-NT versions of Microsoft Windows (described by MS themselves). I found that a bit of a drag, so I set out to circumvent it in one way or the other. The theory is simple: Install a 512 MB RAMDrive before Windows boots, and use that as Virtual Memory (swap).
Problems
- Windows ME skips both config.sys and autoexec.bat in the boot sequence.
- The standard ramdrive.sys supports max 64 MB per drive.
Solutions
- Install the Real DOS-Mode Patch for Windows Millennium (local mirror)
- Use a alternate RAMDrive (local mirror)
But, that still didn’t quite solve my problem. Sure, I used all 1024 MB RAM, but Windows complained about “Not Enough Memory” when starting a DOS prompt. So, in addition, I used both of the tweaks from the MS article and added some lines to my system.ini:
- Under the section [vcache] I added MaxFileCache=131072. This will make Windows use max 128 MB RAM for file cache, which in all cases is a good thing. If you want more, just set it to the full 524288 (512 MB).
- Under the section [386Enh] I added MaxPhysPage=80000. What this should do, is to make Windows use at max 512 MB RAM. For some reason it is in MB, so I actually told it to use 524288 MB RAM, but it works nonetheless. If it doesn’t for you, use MaxPhysPage=200 or MaxPhysPage=512 instead.
The line I used for my RAMDrive in autoexec.bat is:
XMSDSK 524288 R: /T /C1 /Y
Notes
- I use a 512 MB RAMDrive because I have 1024 MB RAM total (1024 total minus 512 limit is 512 left for drive), but for people with 768 or 640 MB RAM total, or similar, then a smaller RAMDrive is probably better. Also, a RAMDrive smaller than 256 MB should not be used for Virtual Memory.
- Doing it in this way, by essentially patching the boot sequence, you probably break your Microsoft Windows Millenium Edition license.
- For users of Microsoft Windows 98 or 98 Second Edition, the Real DOS-Mode Patch for Windows Millennium would not do anything, and should not be installed. Asides from that, the XMSDSK should work with 98 and 98SE, as should the system.ini changes.