Re: Stability of 15 MHz ZipGS

[harold.h@genie.com (Harold Hislop)]

Mitchell,
 
What you're describing sounds to me like your Zip isn't exactly stable
-in the machine- you have it in. (stability at high speeds can be
very machine specific, even affected by other cards installed)
 
First off, try a slower clock speed... maybe 56Mhz or even 50Mhz. If
this 'fixes' things, then you likely have to accept a slower speed (hey
it's still better than you had before :)
 
If that doesn't cover things, look at the cache ram you have installed.
It is best if the TAG chips are around 15ns and the DATA chips are 45ns.
This configuration eliminates a bus contention problem that usually only
shows up at high speeds. (Personally I like ISSI or Winbond 15ns parts
for TAG, and Mosel 45ns parts for DATA. AVOID Motorola like the plauge,
they usually operate faster than rated and this exacerbates the problem)

--
-Harold Hislop
Hardware Coordinator,
Apple II RoundTable, GEnie
14Mhz/32k TWGS, 1Mb Rev-C RamFast, Prototype ROM_03 in tower
Heritage Mac hardware also spoken (great IIgs peripherals :)