IIGS 1 meg RAM card - trouble-shooting?

[buggie@ben09.unm.edu (stephen e buggie)]

     I have a IIgs RAM card that jams up the computer. No damage, but when
its in the slot, a get a large-square "checkerboard" pattern on the
screen, and nothing boots up.  Not even the self-test will activate.

I also have another flaky IIgs 1 meg RAM card, and propose to socket-ize
the controller chips to get one wroking card out of two dead ones.

But WHICH CHIPS should be tested first?  Installing sockets is no picnic
so I want to minimize the number that have to be done.   Neither card has
any obvious physical damage.   (The other card always gives an error of a
bad chip in a particular chip location, regardless of which chip is in
that socket.)

The advice I seek is to have an expert list the controller-chips that
should be checked, from "most probable" on down...    Thanks!

Steve Buggie


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