> I shorted the TEST SW to ground and got into the Utilities menu and ran the CPU test. > It was a bit hard to read the menu so I followed along with what was in the manual. > So now I have a starting point for replacing the RAM chips. > This board was sold as "working" but there were popcorns in the box which probably > created the static that blew the chips.
The suspect chips share a common output enable signal (/TROE.C1X). I'd check that out first: it originates at pin 17 of the 74ALS541 @ U43, which has a 100 ohm resistor on its output.
Otherwise, here's a source of VRAM chips if you need them:
http://cgi.ebay.com/?viewitem&item=390601177814
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