Amiga 1200, Virtual Memory?
 

I have an Amiga 1200 & Apollo 1260 (32mb RAM)

As it is a desktop, I cannot fit another 32mb SIMM and I will not towerize it...

As some demos and games (Quake II) require 64mb, I was wondering if virtual memory was a possibility? :confused

not without using the MMU, which AmigaDOS doesn't.

My Apollo has an MMU & FPU. Can this be used?

Krhm... VMM
Dunno how usable it is, haven't tested it myself.

Ooooo I'll give this a try :)
Cheers bud

:) there's also GigaMem 3, look in EAB ftp.

I couldn't get them to work, oh well.... :crying

A certain Polish Wizard can solder a 'flat' SIMM socket on for you, that way you can use 64MB in a Desktop case :)

Really? Any idea where to get the sockets? I'm assuming the trapdoor would bulge quite a bit with one installed?

I already sent him my knackerred Apollo to try and fix. Both my cards are socketed, so would need to be desoldered again and the CPU's soldered directly to the board, I think, for there to be enough space. I might ask him to do this for me sometime. I'm reluctant to leave my Apollo @ 80 in the hands of the post, they lost my precious GVP Simms :mad

Can some wizard alter the bios to accept 64mb Simms? That would be ideal! (Probably not as it would have been done already) :sad

There were some pictures on AmiBay somewhere, sorry don't know any more details.

I'd have probably kept my Apollo 1260 if I'd know about that 64MB mod :agree

I got this done by said wizard! Very professional and impressive job!

Rather than soldering a flat SIMM socket it's the SIMM itself which is soldered to the board using some "L" shaped pin array. Neat mod.

Cool, people have been trying to do this for ages and finally we have a solution :xmas

I've seen that done. The only thing that bothers me is if the SIMM became faulty it would be an absolute nightmare to replace it. In fact it would possibly be easier to replace the faulty IC rather than the entire SIMM.

Some images from stachu100:

https://picasaweb.google.com/1101219...DesktopProject

That guy's got the skills :)

Regarding the 32MB limit per SIMM, it seems to be a hardware limitation (e.g.: not enough address lines on PCB), which can’t be by-passed by means of a BIOS update. May be some other knowledgeable user can explain this better than me.

There was some time ago a bit of discussion about Apollo's memory:

http://eab.abime.net/showthread.php?t=72049

@ShK: Thanks mate, that’s were I’ve read about such limitation.

A bit off-topic, but what about the BIOS? Has anybody ever tried to dissassembly it and document its contents? Could a stable 100MHz mode be achievable through proper optimization of its code?