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MDD'03 reports 1.99GB of Built-in Memory under OS9?
Posted by: Trash80toHP_Mini on 2026-01-20 16:34:53
While I was trying to get drivers installed for the new VidCard, I started to play with RAM sticks to try to pinpoint the system memory check error that cropped up on every boot. First thing I tried was pulling the stick from J20 and the error went away! Still reported 1.5MB available as it had always done before. Pulled the stick from J23 the next slot over and replaced it with the first one I'd pulled, same same, not the stick apparently. So I put the J23 stick into J20 just to see . . .

1.99GB_reported_under_OS9.jpeg

So now About This Computer reports 1.99GB of Built-in Memory? I've never seen such a thing before and never expected to see anything over 1.5GB!!!!

LEM says: RAM: 256 MB standard, expandable to 2 GB (although Mac OS 9 will only recognize 1.5 GB) using PC2700 memory in 4 DIMM slots

WTH? 😱


edit: just noticed, with the OS hogging 562.7MB and Profiler another 4.4MB, it's still reporting Largest Unused Block as 1.42 GB?????
Posted by: Powerbase on 2026-01-20 17:04:22
My understanding is that this is standard behavior. It can recognize how much is installed, but cant use it. Hence Mac OS "using" half a gig.
Posted by: Trash80toHP_Mini on 2026-01-20 17:17:58
Beat me to it. Thanks.

Picture 11.jpg

Seems to be behaving like unclean Macs running without MODE32 addressing memory over 8MB.

But 1.99GB? That's just strange. Sure would be nice to have an OS9 extension like MODE32 for that extra half gig. 😉
Posted by: nathall on 2026-01-20 22:59:08
Most of my 2GB hard drives also report 1.99GB total space when looked at in the OS 9 Info window. Must be some kind of weird math glitch with OS 9.
Posted by: Trash80toHP_Mini on 2026-01-20 23:38:04
Yep, strange thing is that when I was getting the memory error on startup with 2GB on board it always showed up as 1.5GB Built-in Memory. I'm leaving the fourth stick out of the equation. 😉


edit: does it matter which slots I populate? Shouldn't I'd think.
Posted by: nathall on 2026-01-20 23:42:00
Ah, gotcha.
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