Hi., I've been using a powerbook (G4,17" screen, 1.67 GhZ, 512 Mb RAM) for the last 15 or so months and as the photo shows, the screen has suddenly gone bust. I thought this was a video board problem, so I connected it to an external display (a 17" CRT), and the external works perfectly fine.I also ran the hardware test (and, based on a suggestion in the apple discussion forums - the techtool pro test) and the video memory checks out. I dropped the laptop on its edge about 6 months ago, but the display did not show any problems then. This has started happening only over the last 10-15 days, and I don't know if the bump 6 months back had anything to do with this. The problem is that I see 'twinning' on the display - I've uploaded a photograph to explain what I mean. It is a bad image, but basically, part of the display left of the white bar is duplicated after the black bar in the center. As in, if I want to shutdown the laptop and go to the blue apple icon on the upper left corner, the mouse arrow gets duplicated and I see two arrows on the screen - one on the left of the black bar and one on the right - when I click on the mouse button to pull down the menu, the apple menu pops down at two locations - on the upper left corner (where it should be), and to the immediate right of the black bar. The red circles mark out the location of the arrow(s) when I shot this image during login. Now, since it is unlikely to be a video memory problem (?), is this a cable/connection issue? I took it to the apple service center, but the apple genius there told me that I'd have to replace the entire display assembly at 700 pounds (1300$). I plan on replace the display myself, but I want to be sure if this is a screen problem or a connection problem. I've opened up the laptop and checked the connections - none of them were loose, and the display still has the same problem. Is there anyway I can check if this is a connection problem or a screen problem? Any tips or advice would be much appreciated. cheers!