What do I check? My Emerson 40 inch LCD TV is perfect every time you turn it on but afte 3 to 5 minutes the picture starts to

[A Jay]

Emerson LCD TV Model LN37A330JLDXZA VERSION PMOL
After it has been playing for a short time the picture breaks up, sections of the picture flash and dart on the screen and the screen gets darker the longer you leave the set on, Every time you turn the set on it is perfect for those first few minutes

 

[i7Baby]

Try a monitor or other TV - to work out whether its the TV or your graphics card.

Post your complete and detailed build.

 

[americanaudiophile]

It seems that your TV has a pretty bad reputation for being very unreliable. Power inverter boards and PCB driver board transformers seem to be common weaknesses. Either way the repair cost is very high compared to the cost of replacement. Sorry.