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LC III system software taking 80% of RAM
Posted by: Pilgrim33 on 2025-08-23 19:28:52
I have an LC III running System 7.5.5 with 36 MB of RAM and the system software is using up ~80% of the RAM (30,699K, see first picture below). I'm running it off of a ZuluSCSI. However, when I boot off a disk image that uses 7.6.1, the system software uses only 2,640K of the RAM.

With the 7.5.5 disk image I have tried booting with the shift key held down, to disable extensions. I have also tried to zap the PRAM (Cmd-Opt-P-R at startup, cycle twice) and I tried rebuilding the desktop on the disk (Cmd-Opt at startup). None of this changed anything.

I also tried a different disk image with 7.5.5 and I see the same usage of ~80% of the RAM by the system software. Is there some known issue with System 7.5.5 and the LC III? Any ideas are welcome!

IMG_4373.jpeg



IMG_4376 (1).jpeg
Posted by: Pilgrim33 on 2025-08-23 19:37:00
Apologies--please disregard this thread. After starting up again from the 7.5.5 disk image, the RAM usage is now back down to 2,045K for the system software. I have no idea why. But, problem solved! 🙂
Posted by: finkmac on 2025-08-23 19:42:17
enable 32 bit addressing if it happens again (sys will use all ram over 8mb if it’s not enabled)
Posted by: Pilgrim33 on 2025-08-23 19:53:31
Ah, great to know! I see that it is turned on now. Thank you!
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