I have an Apple Powerbook G4 which has been dropped. The screen is physically intact, although one hinge is broken so the screen is attached to the main case at one end only. When it powers up, the display is 'scrambled' flickering horizontal lineswherever there is an image. I've hooked it up to an external display which displays fine. I've opened up the main case and screen casing & 'jiggled' cables, disconnected cables, etc, but no change to the display. Do you think it possible to determine which component is the source of the image problems. As I say the LCD unit itself looks intact.