Power light blinks 7 times but won't turn on

If it is under warranty call the retailer or the manufacturer to setup a service call. The problem could be your y-sus or y-buffer boards. Without seeing the TV and performing diagnostics on it, it is impossible for me to say for certain.

You can also check here: http://www.avsforum.com/avs-vb/showthread.php?t=1001318