Hook it up to a external monitor to try to isolate the problem. It could be as simple as a PRAM battery or as complex as a failed GPU.
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Hook it up to a external monitor to try to isolate the problem. It could be as simple as a PRAM battery or as complex as a failed GPU. You can also get to the hard drive by starting it up in "Target Mode" by connecting to another Mac via a firewire cable and starting the G4 up holding down the "T" key. Your hard drive icon should appear on the desktop of the other machine.