View Full Version : System 7.5.3/7.5.5 and VM

July 15th, 2007, 03:01 AM
I can't seem to change the virtual memory settings (or even enable virtual memory) in system 7.5.3 or system 7.5.5.

The memory control panel has only disk cache settings, and the version number it displays is 7.5.5 in either version of system software.

The computer is equivalent to a mac plus (It's in an emulator).

"System" 7.5.x means "Mac OS" 7.5.x. It was called system software back then.

July 15th, 2007, 10:11 AM
I think you need a 68030 with mmu for VM, a Plus is a 68000 I believe so you cannot have VM.


You are stuck with 4MB of RAM max.

July 15th, 2007, 10:30 PM
Mini vMac, the emulator I'm using, does emulate a PMMU. Most other mac emulators don't, so yeah. The mini vmac 3 alpha seems to have an (compile-time) option to emulate a 68030 instead of a 68000, so if I can work out how to compile things then I will do that.

Thanks for the info!


P.S. for those who are interested, Mini vMac can be found at
You need to own a Mac Plus, Mac SE, Mac 128k or Mac 512k to use it LEGALLY though.;) (You need the ROM file.)

EDIT: It's actually 68020 , not 68030. Not sure if it'll work, but it' worth a try.

August 17th, 2007, 12:24 AM
Upon performing more research, there are a variety of third-party programs available that will do virtual memory (and RAM compression etc.) on processors prior to the 68030. I recommend Ram Charger. Google it.