I have the same issue with a Samsung un65nu8500. I can disconnect any one of the 4 connectors and it boots without issues, just no display. As each of the 4 cards are attached to the led screen with 3 ribbon cables I do not understand how disconnecting any of them does what it does but to be honest I do not know much about the led sheet itself. It sounds like the only fix is to replace the led screen itself. The replacements I have seen are running around $900 Any other ideas out there or just salvage the boards and sell them on ebay?

I have had the same issue with the 8500 tv. If I disconnect 1 of the 4 ribbon cable for the led screen the TV will boot. After talking with Samsung they say the only way to correct this issue is to replace the actual screen that has these ribbon cables built into them. Replacement screen = $850 which is what the TV cost.