How to check for faulty chips?

[smittie]

Hi guys,

In my previous post, 'Is my VIC-20 fried?', I asked for advice on how to fix my VIC-20 that didn't seem to power on. I therefore determined that the power supply was giving an overvoltage to the computer (5.8V) So I ordered a new power supply from Ray Carlsen. It worked like a champ for a few days, but today, I tried to fire it up to no avail. It's giving me the same problem as before. The LED light is lighting up, but to signal. I hit a brick wall and I don't know what to do. I know that overvoltages attack the RAM first, but they are all soldered into place with no sockets. I don't have spare RAM chips, so I am now asking for any directions on how to test the RAM without de-soldering them, perhaps with a multi-meter. Also, I am wondering if anyone know what other chips might have been attacked by over-voltage. Any advice is appreciated.

Thanks! -Smittie

[beamrider]

If the computer won't boot - you can't test them without de-soldering other than seeing if any are getting very hot.

Any chip can potentially be damaged by over-voltage.

[smittie]

Good news, the fuse just blew I just want to give up at this point... this is just so hard