iMac Bondi G4 stopped booting

[kahlil88]

Haven't touched my Bondi G4 in 9-10 months and come to find it no longer wants to boot! No chime except after a PRAM reset, won't boot from hard drive or optical drive. I was able to partially boot an OS9 disc only once, but it gave me a memory error and hung. I've tried swapping the RAM around or just running one module at a time with no success. My hunch is it finally needs a re-cap after 24 years or it's a CPU issue.
The heatsink doesn't feel as snug since the G4 upgrade, very likely because the original chip had a gasket/shim around the edge that sat flush against the heatsink and it's missing from the new CPU so it's very easy to wiggle even with the tension clip on.

 

[kahlil88]

It's alive! Thankfully just turned out to be a combination of a dead battery, bad RAM (idk how it died just sitting but ok) and using an OS9 disc it doesn't like (9.2 worked fine, maybe 9.1 is confused by the G4).

 

[Phipli]

The heatsink doesn't feel as snug since the G4 upgrade, very likely because the original chip had a gasket/shim around the edge that sat flush against the heatsink and it's missing from the new CPU so it's very easy to wiggle even with the tension clip on.

Likely the new CPU is a different height slightly.

 

[kahlil88]

This started happening again and now I'm thinking capacitors/PSU may need some attention. Powered it on a few times this evening, often no chime and the only sign of life was I could eject the optical tray. Then sometimes it would chime but no power light or monitor. After sitting awhile it suddenly chimed and came to life by itself and has been working ever since.

 

[3lectr1cPPC]

Sounds like caps to me, good luck. These iMacs have a lot of them.