Yesterday I bought and installed a 120mm (main system fan) and an 80mm (power supply) to replace the loud stock fans. After this it won't boot at all. When I press the front power button it just powers up for 1-2 seconds and then shuts right down again.

I tried taking out the mobo battery then pressing the pmu reset button just once and leaving it overnight. Then this morning I put the battery back in plugged power back in and tried to power it up. Same problem..

I have also tried unplugging the drives and new fans but still no go.

Any ideas or tips?

For the record its a G4 400 with a G4 1GHz upgrade, 1GB RAM, 2x80GB HD, and a DVD-RW
Mac mini C2D 1.83GHz - 2GB RAM - 200GB 7200rpm HD
Sawtooth w/G4 1GHz - 1GB RAM - SIIG SATA w/2x1TB HD
B&W w/G4 600MHz - 1GB RAM - 2x80GB HD
Sawtooth G4 400MHz - 512MB RAM - 40GB HD
Dell Ultrasharp 2007WFP 20" Widescreen LCD
2.94TB Total Storage