can the iBook start up at all? obviously, the system and hard drive are fine, if you can target disk and boot from it. i'd say start it up, and see if you can see any type or display on the screen (may have to look really closely). or perhaps if you have the video out adapter available, plug that in, attach to a monitor, and see if it mirrors. if it does, then maybe the display in the iBook is just bad.
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