iBook G4 only runs w external display

I picked up this iBook G4 12" 1.07 from a friend of mine as an organ donor for my PB 12"(switched the LCDs) It had a dead hard drive in it and I supposed it was suffering from the logic board problems, but the screen lights up and stays in grey. It will hook up to a VGA screen and runs fine with that. My question is: if it was indeed the video chip that was unseated would it display on the VGA at all? Is this a cable problem? Could it just be the cable running from the logicboard to the display that is chewed up(possibly in the hinge area)?
I popped it open and tried to see if the connector on the logic board was loose, but that didn't help.
Anybody had this problem?

Anybody?

So essentially my question is: can I get this bad boy up and running again or should I chuck it?
It just seems to me that it is not the typical video card issue, but don't know enough about it to make the call.
Anybody have an idea?

Great - thanks.
I guess I'll try to save it from the landfills then.

Still no signal

So I replaced the display cable and put it back together. Still no signal coming up on the lcd. It still comes on brightly - but grey. Could it be the inverter board or does this mean for sure that the connector on the logic board is bad?
When I boot in target mode it mounts to my other computer but the firewire/target screen with the bouncing logo doesn't come up on neither screen (built-in LCD or external VGA) - don't know if that tells anybody anything.
Appreciate any input - thanks!