I had a very strange incident this evening. I was watching TV on the computer and suddenly the sound stutter. Some seconds later, the screen went black. First I thought ok some error, don't worry. Since the computer didn't react on any input from the mouse or keyboard, I shutted it down by pressing the power button.

I tried to reboot but the monitor rest black. All the fans were running, the MB didn't made a beep and the leds are all green as they have to be. The HDD is running too, also the monitor is on. But nothing happens, not even a single message on the screen, just black.

Here are the things I already tried with no success:

• tried to boot with 1 of two rams (each tested alone)
• turned off all power (pull th plug) for 10 minutes
• tested the graphic card with another pc. there it worked.
• tested the RAM with another pc. there it worked.

Any hints what to do next?