Mac IIci cache card

Brutus75

New Tinkerer
Aug 15, 2025
26
1
5
3
Hello all,

Is there anyway of telling whether the cache card installed in my Mac IIci is working without having to run benchmark tests? Or is that the only way?

Thanks
 

phipli

Active Tinkerer
Sep 23, 2021
364
250
63
Hello all,

Is there anyway of telling whether the cache card installed in my Mac IIci is working without having to run benchmark tests? Or is that the only way?

Thanks
Its the only way. They're invisible to software. The Apple ones are at least.

Its easy to tell though, before and after is a double digit percent difference in CPU performance in something like System Info.
 

speakers

Tinkerer
Nov 5, 2021
161
100
43
San Jose, CA
peak-weber.net
MacTest Pro will tell you whether the cache card is present and working.

Also see the IIci Developer Notes for the memory addresses of the cache data and tag RAM that may be pokeable from MacsBug (I haven't tried).