Often times, the capacitors in monitors and TV's that are in the power supply will go bad and cause the display to act up as soon as they have time to charge. If you take apart the TV and look at the capacitors (Probably the tallest cylindrical component) and see that they have a slight or large bulge in the top of them that means they are bad. In that case read the numbers on the side of the bad ones and replace them with an equal or greater valued capacitor. The metal part on the top of the capacitors should be completely flat.
Hope this works.