TWGS upgrade problems

["Tim Haynes" <timhaynes@no.spam.please.alumni.uwaterloo.ca>]

Hey everyone,

I got my mouser oscillators today, and just finished trying them out.  I am
using a stock ROM 01 with 1MB of RAM to test.  My TWGS has the Western
Digial 14MHz CPU.

I tried the 40, 48, and 50 MHz crystals in that order.  Continual self-tests
ran fine for a few minutes.  Then the self-test died with the 50MHz crystal
while doing the "non volatile memory test".  It just locked up - no screen
garbage.

Now when I boot, all I get is a white screen with one black block in the
upper-left quadrant.  I went back to my 28MHz crystal, and still get the
same thing when I boot.  Even waiting a while doesn't fix the problem.
Tried moving the TWGS between slot 3 and slot 4, wiggling the oscillator,
pressing down on all socketed chips & the ribbon cable sockets - still no
good.

When I remove the 32k cache board, I get a pure white screen (no black
block) but the black block comes back when I put the cache card back on.

Is it possible that I've destroyed my TWGS?  I'll I leave it for a few
hours/overnight but am not holding much hope.

Thanks
Tim