The pre-800MHz G3 iBooks were prone to problems like these, and I believe there was a recall due to more than 50% of logic boards being bust. And they say all that comes out of Cupertino is pure quality...
So. Could be overheating, logic board failure, video card failure, or a circuit short.
Or Gremlins.
Take it to your local Genius bar or if that is inconvenient, get Googling.
So, I'm a sucker. I bought a G3 iBook on ebay that promised that video worked, turns out it has the dreaded failed solder balls. After I tried fire-reflowing it myself, the iBook wouldn't turn on. A day later it would turn on, but would shut down before the OS could load. Now I can wait a few hours, it'll chime and start, but shut down before the video can start.
No amount of PMU resetting has solved anything.
Thoughts?
TIA!

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