ZIP/GS SRAM Problems

[ae196@FreeNet.Carleton.CA (Dan Markarian)]

Background:
 
I have made "The 14MHz" modifications to my ZIP/GS quite a while ago, but
RAN into certain problems with the SRAMs (20ns 32kx8).  Running short on
time, I configured the ZIP/GS to 16k (in place of 64k) and installed a
slower 45 MHz oscillator (CPU @ 11.2MHz) to stabilize my system.  It
worked.  I didn't ask questions.
 
Now that I have time again:
 
I'm trying to figure out what my problem with the ZIP/GS is, and up its
cache (and later its speed) a bit.  Could anyone help me isolate (or at
least point me in the right direction) my problem?
 
With the 4 SRAMs populated, the system runs fine configured at 8k or 16k,
but seems to crash within the first or second minute of operation at 32k
or 64k (operation -> ie. booting GS/OS, operating Finder).
 
With only the 2 SRAMs installed in the leftmost two sockets, the system
runs fine at 8k AND 16k [the fact that the latter worked threw out all
of my amateur concepts of how the SRAMs are mapped on the ZIP/GS].  At
32k, again, crashes within 1-2 mins of operation.  64k not attempted.
 
Could I have bad SRAM chips?  Or bungled my soldering job?  Or possibly
NOT have 32kx8 SRAM chips like I think I do?
         ~~~~~
If it is any of these, or other problems, could you suggest how I could
go about to find out for sure?
 
Thanks in advance,
 
Dan Markarian