spacemannot,
It could be a power supply or a mainboard issue. These issues are best diagnosed by a service tech. Without actually looking at the unit, it's almost impossible to determine the cause.
--HDTech
I have a friend who has a big TV, id say its 30-40"? well its got this problem, when it is turned on it will stay on for a minute or so, flicker on and off then the screen will turn off. but the power for the tv is still on. is there a way to fix this? and what would be causing this?

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