I‘ve got Quadra 605 with motherboard 820-0364-A, and ASTEC AA16251 power supply. I’ve recapped both of these using caps from Console5. The motherboard caps definitely needed replacing and did cause some damage to the -5V trace near C36, which I repaired with a bodge wire going to the -5V connection on the bottom of the board. I was able to verify connectivity to the following -5V pins:
I’ve read that not having a battery can cause the no video problem, and since I did not have a good battery on hand I attempted to use 9V to 3.3 V power converter to see if that would fix the no video issue (without success). I realize its not quite 3.6 V but assumed it would be close enough. I’ll get a proper battery soon to rule this out. I’ve also tried the power ”on/off/on” trick to work around the no video problem too.
I’ve verified the that the power supply is providing -5V, +5V, +12V. I’ve reseated the RAM and Video RAM, but have not attempted to use Deoxit 5 on those connectors.
Any ideas on what I can probe to see what’s causing the sad mac chime? Best I have is a voltmeter, so I‘ll be limited in what I can check.
- U30 DFAC-II pins 6, 5, 15
- U21 26LS30 pin 10
- U22 26LS30 pin 10
I’ve read that not having a battery can cause the no video problem, and since I did not have a good battery on hand I attempted to use 9V to 3.3 V power converter to see if that would fix the no video issue (without success). I realize its not quite 3.6 V but assumed it would be close enough. I’ll get a proper battery soon to rule this out. I’ve also tried the power ”on/off/on” trick to work around the no video problem too.
I’ve verified the that the power supply is providing -5V, +5V, +12V. I’ve reseated the RAM and Video RAM, but have not attempted to use Deoxit 5 on those connectors.
Any ideas on what I can probe to see what’s causing the sad mac chime? Best I have is a voltmeter, so I‘ll be limited in what I can check.