Let me start by saying I'm a first-time MAC user so my MAC knowledge is pretty much non existent. I have an older iBook G4 800mhz 12”. When I turn it on, I can hear the hard drive spin up and the fan runs, but the screen remains blank (absolutely nothing). I let it run for several minutes, but still nothing. In this state, I can’t power off with the power button (have to remove the battery) and I can’t eject a DVD stuck in the optical drive. Any suggestions? I’m not afraid to tear into it if I can look for specific issues.

I've also tried leaving the battery out for >15 minutes, resetting the computer's parameter RAM, and resetting the computer's PMU - NO LUCK, still blank screen.

It is most likely a logic board problem which is fairly common on that model. It may not be worth fixing at this point.

Thanks for the advice. Does anyone know if the MAC stores will do free diagnostics? If it's a bad logic board, is it worth parting out on eBay or something?