On Tue, 30 May 2000, AstroZomby wrote:

> In any case, are all the 16Mb SIMMs the same speed?  And, are they all FPM?

Within each bank the simms are all the same speed.  I have tried different
speed SIMMs including 60ns, 70ns, and 80ns.  They are all faster than the
120ns minimum documented by Apple though.

I have no idea if they are FPM or EDO.  Is there an easy way to tell?  I
have tried the 4MB and 16MB SIMMs sold here: http://memoryx.net/maciicx.html

What kind of failure can I expect with EDO simms?

> Mode 32 is all that you should need to address more than 8mb though.  What
> system are you booting MacSide though?  7.0-7.5.5?

I'm using 7.5.5.  NetBSD seems to rely on the MacOS probed memory amount
rather than doing its own memory probing.

> I've got a MacIIci that has no trouble reading all 8 slots with 4mb simms
> in MacOS 7.5.3, however, have not had my hands on any 30pin 16's yet.

>From what I've been reading, the IIci is a lot more flexible than the IIcx
in what types of memory it can use.  Maybe they're more similar than they
appear though.

Here's the behaviour I've observed in my IIcx:

Bank A  Bank B          Result                          Result OK?
------  ------          ------                          ----------
4x1MB   empty           System boots, sees 4MB          Yes
4x1MB   4x1MB           System boots, sees 8MB          Yes
4x1MB   4x4MB           System boots, sees only 8MB     No (should be 20MB)
4x1MB   4x16MB          System boots, sees only 8MB     No (should be 65MB)
4x4MB   empty           Chimes of death                 No (should be 16MB)
4x16MB  empty           Chimes of death                 No (should be 64MB)
4x4MB   4x1MB           Chimes of death                 No (should be 17MB)
4x16MB  4x1MB           Chimes of death                 No (should be 65MB)

No matter what I do I can't see more than 8MB.  8MB is a suspicious number
because it's the same as the 24-bit addressing limit imposed by dirty
ROMs, but I am running MODE32 and 32-bit addressing is enabled.

Thanks for your help.
-- 
Tod McQuillin