> I was out most of this evening, but I just had a quick look again and think I have > found something significant. Comparing the gate array pins on the two boards I > have, I see that on the board where the video is corrupted, there are two pins > that appear connected to 0V that are not connected to 0V on the spare > motherboard. > > I have yet to attempt to trace the connections to these pins, I will do that > tomorrow as it is late here now, but I suspect it does not bode well for the gate > array :-( > > Regards
I have made an interesting, but sad, discovery. I traced both the two apparently shorted pins on the gate array to two pins on the Chips & Technologies 82C206 Integrated Peripherals Controller. Checking the 82C206, I found lots of pins on that chip appear shorted to ground. I fear the 82C206 has failed badly. I suppose that, happily, it looks possible to procure replacements for this chip. I am slightly puzzled by the packaging of this chip though. It is surface mounted on my CPU board, but the packages available for this chip are PLCC which I assumed required a PLCC socket. Can PLCC chips be surface mounted, or is it a subtly different packaging that I would need? There is no obvious damage from battery leakage near this chip, it was close-ish to the damage area but the leak didn't reach it, so I think the failure is either due to other damaged bits causing it to fail, or just plain old age. Is there anything I could have missed that might make me think it is faulty when it isn't? Regards Rob
