ibook G4 1.2 Constant Aggrivation

ibook G4 kept starting up to the gray multi language "kernel Panic" reboot screen. After reinstalling 10.3 from orig cd's multiple times I sent it, during Apple Care Warranty, to an authorized service center. It came back with new HD "retainer clips" and a new install of 10.3. They said it is fine now. "Everyything tesed ok. Hard drive, Logic Board, Ram, with the exception of the ethernet jack being a bit "sloppy"... Nope, not ok; Then, in no particular order, it would do any of the following, Spinning gear on blue screen all day long, white screen gray apple logo freeze (no spinning gear) White screen gray logo freeze and the logo itself shifts to the right and down just about a half inch then freezes. Works ok for a while then safari (when being used) stops and color wheels until you hard reboot. I then sent it out again and they said "well, we reseated the hard drive and put in new battery (my old one was not on the list) and tightened up the hinges. Get it home all excited and boot it up to all and any of the same listed above. I have removed RAM, Airport card, Target disk mode installed, formatted with all zeros... Reset PMU PRAM etc...
I'm honestly thinking Logic Board here. Now Apple Care is over and they will not admit that the problem exists (we won't go there.)

Are there any thoughts on this one? I'm open to suggestions. broken solder joints, bad flex ribbions inside, Is the hamster tired?

By the way; AHT says all is good.

Thanks for your help.