1. Inspect all the caps for "bad caps?" (google what to look for.)
2. Go ahead and replace all thermal compound?
At that old you might have to scrounge another one from Ebay or such.
Hi there,
I know this is ancient technology now but I'm trying to get my old G4 Quicksilver tower back into service (I want to run some OS9 apps) and there's a problem with it that I'm finding hard to diagnose.
Essentially, the machine boots up fine but after two to three minutes cuts out to black screen with lighted on/off button on 22 inch Apple Cinema Display blinking rapidly. Power button on display and on front of G4 are then completely unresponsive and only 'fix' is then to uncouple power cable and replug, allowing same brief boot up as before.
I'v tried replacing PMU battery and pressing reset button but that doesn't work.
I'm guessing it's some kind of thermal issue?
Anyone able to shed any light on this?

Chowhound
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