Ok. Plugging the cord into the wall brings up the red stand-by light. Pressing the power button you can hear the fan start up for a moment, then about 5 seconds later it shuts down. Red stand-by light disappears. Must unplug, then plug cord back into outlet for red light to reappear. I have bought a Power Supply Unit but that did not fix it. I do believe it was a different model then the one that was in it if that matters. Is it the power cord? The Power Supply? The Power Ribbon? Please help so desperate :(