Mitsubishi WS65511 Rear Proj. TV still have resetting problem after DM caps & conv. IC replacement. Any other ideas or tests to do ? Any TV old timers that remember how to diagnose boards ?

My Mistubishi WS 65511 Rear Projection TV runs fine for 15 minutes, Then kicks off & has the blinking green light while it resets. You can turn it on again & get another 15 minutes. Over & over, Then it may work fine for 6 hours or more. Seems to be worse when cold. And the problem has been more frequent with months. So I replaced the 7 Elec. Caps on the DM board. They weren't bulging & looked fine, But I put in 7 new ones. Did not improve at all. Same problem, Same time, 15 minutes. While in there I looked at everything. Nothing bulging, burn't, or visual. Something is going bad & causing a over load that triggers a shut down & reset. Any Help or Ideas PLEASE ! Any possible parts that I can try that might have done the same for you. I can solder in parts, But don't know what to try with it being so erratic. Also, does anyone have a service manual with wiring diagram. OR should I just try buying used boards off EBAY & try replacements. I really want to keep this monster in the living room. I've grown accustomed to her face. And the wife likes to pile nick-nacks on top. There should be lots of these replaced with flat screens by now. When it works, The picture is perfect, sometimes all day long.