Hopefully someone might be able to offer a little advice regarding my issue... I have a 17" G4 Powerbook that was running fine until the notorious power adapter shorted out on me. I purchased a new power adapter which charged the battery but also created an awful squeeling sound from the adapter box. When I go to start the computer it either starts only up to the gray logo screen then shuts off...or only starts the fans running without video and then shuts off. Apple Genius (without performing a full diagnostic) said it is probably my Logic board and/or DC-in board and recommended replacing them. But heres the kicker... When I removed the battery and plugged in the adapter...there was no squeeling and the computer fully starts and seems to operate without problem. Logic board issue? Bad battery issue? Please help! Dont want to replace logic and DC-in boards if I dont have to!!!! Thanks!