G4 Powermac won't start.

[supachicken]

Hi Guys,

I have a G4 powermac that won't boot. It was originally a G4 400MHz sawtooth but has now got a dp500MHz upgrade, it had been running for a bout a year with the upgrade.

When I try and bootup it just doesn't do anything and there is no sign of anything booting, do you guys have any idea what may be causing such a problem?

Cheers.

[mad jew]

Could a power surge have fried the adaptor? It's hard to say because it really could be a multitude of reasons.

Does it make any attempt to start at all? If not, I'm guessing it's a power issue.

Just for the record, what were you doing just before it stopped working?

[mkubal]

Does the power button on the computer light up at all when you press it or is it completely dead?

If it's completely dead my first guess would be a bad power supply.

[iEdd]

Sounds even as simple as just a problem with the power switch. Have you got a monitor with a button on it you could try?(ACDs generally have the button for the computer on them) Otherwise it could be a faulty Power supply.

[840quadra]

You can try to reset the PMU on the motherboard. I have had to do this on my B&W G3, and my G4 Digital Audio.

Directions from Apples website.
http://docs.info.apple.com/article.html?artnum=95037