Received an iBook G4 that will not boot, but will power up. On occasion the fan starts. Cap-lock and NumLock indicatiors light up. But no display. No startup sound. If I slap the Ibook on the backside several times it will boot normally...run for a while then go back to the black screen...sometimes the fan will keep running but no display. When it receives no pat on the backside it powers up with no display, no sound...just maybe the fan will run. Tried resetting the PRAM, PMU.
I'm thinking the logic board....but why then will it start with the slap on the back.