It could be as simple as the capacitors like in the Samsung power supply problems. Someone reported that the power boards in Panasonic displays were actually made by Samsung at least in some of the Panasonic displays. I don't know if this is true or not though.
I am fairly sure there is some kind of post sequence since these HDTVs are computer controlled, but I do not know which order the boards start in. You would need to buy a service manual to find out.