How do I verify that I have a faulty RAM chip?
Verifying ram chips is a bit difficult exept if one gets very hot or stays cold (while others warm up). But if your amiga was supposed to be working before sending it to you then i would expect a loose contact in one of the custom chips. I saw green screens often which were caused by a bad contact from the agnus chip. So maybe check the Agnus (again) to be sure. Also what you can try is to exchange the CIA's in case one of them is causing the problem. First off all you should try the amiga without the expansion ram board and only replace it when the amiga is working again (then you know for sure the ram board is not causing any trouble.) If possible try another powersupply and if all fails then maybe its best to replace the ram chips with sockets and find some other ram chips to test the amiga with.
I'm not sure if the ram chips should get warm or not in the A500 but if you can measure if the chips get power (5v) then i guess the temperature is allright.
Good luck!
Tom
