I've had this problem in the past, but i seemed to fix it each time, but this time i cant get it to work. I was trying to put a cable in my pc the other day and when i moved my pc forward a little, my pc shut off right away. Now when i try to hit the power button, my fan lights will flash on, then turn off. This has happened to me in the past, where i would go to turn on my pc and it wouldn't put no power. Then i would rest the cmos on the motherboard, a few times, and it would boot up. This time, i went and bought a new 500 watt power supply and the same thing happened. Now i put the new power supply through my power supply tester, and i couldn't get the -5 v to light up, but my old power supply would light up all green. So I think either both power supplies are bad, or the motherboard is shot, or I think some piece of metal is hitting the case, and is causing a short. If the short problem, will my pc work once i fix the metal piece or screw that might of fall behind the motherboard. I think i should take the pc completely apart and plug everything in and see if it works, if it doesn't boot, then I duno what to do. What do you guys think could be the problem?