G4 computer falls asleep every 3-5 seconds

My family's G4 power mac goes to sleep every 3-5 seconds. I've tried resetting smc, pram, getting firmware updates, turning off sleep, and cleaning the fan. Nothing seems to work. I assume it's a software issue, but it could be a hardware issue. I'm wondering what you guys think.

Do you know what model the G4 is? PowerMac tower by chance? My PowerMac G4 Digital Audio did this very thing and it was a bad PMU chip on the Logicboard. Found a board on Ebay for $25 and it's like new again.

Is it really just going to "sleep" or is it shutting down/powering off completely?

- Nick

Yes, it is sleeping. I can wake it up my clicking or pressing buttons on the keyboard. And yes, it is a power mac G4 tower. So, it's the logic board, you say?

apple sam said:

Yes, it is sleeping. I can wake it up my clicking or pressing buttons on the keyboard. And yes, it is a power mac G4 tower. So, it's the logic board, you say?

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In your case I am not 100% sure, but mine started that way and did it more and more to the point I could not even keep it awake. I reset everything and nothing changed. It was a bad chip on the board that controls Power Management. New board and it's like new.

If it does turn out to be the Logic board, I have found some really good deals in the past on Ebay.