Why is the Display flashing?

display cable is not afffected by the display angle. i think it is the graphic card, since i did a repair for my customer last week with the similar failure on the sam machine as you have- she told me that display started flashing and then turned black completely - it was the backlight-enable signal from graphic card that was causing the problem. I did a little hack described here http://forums.macrumors.com/showthread.p... and screen is running again.

but it could be the ccfl inverter also.