Re: Trouble upgrading a Zip GS

[supertimer@aol.com (Supertimer)]

livepoet@together.net (Kevin Smith) wrote:

>I've had some trouble while performing upgrades on my ZipGS card.  So
>far, what I've done is replaced the processor with the 14Mhz one from
>WDC, gave it a faster cache, and put in a 64Mhz oscillator.  However,
>when I turn on the computer, it doesn't boot up.  The upper left part
>of the screen is black, and the bottom right part is a blocky white
>shape.  I have a Focus harddrive card, and I can see its activity
>light go on when I turn the computer on, and it goes on each time I
>reset with control-apple-reset.
>
>What could be causing the problem?  Is the oscillator too fast?  Do I
>need a stronger power supply to support the extra speed?

The pattern you describe indicates the ZipGS is locked up
which means it won't function at 16Mhz.  Actually, few
ZipGS units will go that high.  The fastest ZipGS I've read
about was 15Mhz (there are TWGS cards running at
16Mhz, though).

The solution is to try slower speeds first.  For example,
a 40Mhz oscillator for 10Mhz speed will work for sure.
Then step up to 50Mhz oscillator for 12.5Mhz speed.
Go up in increments until you find the maximum speed
for your particular card and IIGS.  It is worth mentioning
that the IIGS that a card is in, not just the card itself,
influences the card's maximum speed.