mattsoft
Well-known member
Picked a beige G3/266 desktop some time ago, listed as working, however when I plug it in, it is dead.
The fan on the PSU powers up, but the power LED does not, no power chime, the HDD or CD drive do not power on either. Bad PSU?
So time to start troubleshooting...
So I'm stumped on this one. The only caps I could not change were the 4 680uF caps on the voltage regulator -- I don't have any replacements in my stash. So I've ordered some more supplies from DigiKey and will replace those this week and see. The service source for this model says to replace the voltage regulator for symptoms like mine, so maybe this is the problem.
The fan on the PSU powers up, but the power LED does not, no power chime, the HDD or CD drive do not power on either. Bad PSU?
So time to start troubleshooting...
- Measured the voltages coming off of the PSU while the G3 was powered on. All voltages are nominal. Check! Strange that the HDD won't spin up with good power (scratches head).
- Installed fresh battery. No change.
- Removed and reseated the CPU, ROM DIMM, memory, voltage regulator board, and personality card. No change.
- Removed the HDD and CD from the IDE bus and this time, but left power plugged in. When powering on this time, the HDD and CD had power. Huh...so being on the IDE bus caused them to NOT power on, but being off the bus they powered on fine. The G3 still did not post -- no chime or power light, but some change from the devices.
- Re-cap time! I replaced all the SMD capacitors on the logic board. They were pretty dry and left little brown turds of dried up electrolytic behind. But the board looks really good. Continuity on all pads is good. Cleaned the board with isopropyl and tried again. No change, still dead.
So I'm stumped on this one. The only caps I could not change were the 4 680uF caps on the voltage regulator -- I don't have any replacements in my stash. So I've ordered some more supplies from DigiKey and will replace those this week and see. The service source for this model says to replace the voltage regulator for symptoms like mine, so maybe this is the problem.