and symptoms. Watch the fans when you turn it on. Do the seem to twitch slightly but stop? If so, something is causing the PS to shut down immediately. This is to protect it and other components. There are other things you can try. Disconnect all drives, pull the RAM and add in cards. Make sure the power switch leads are properly connected to the MB and try again. If the fans stay on, something you removed is the culprit. If nothing happens, you're probably looking at the MB or processor. You can pull the processor as well to narrow things more. This is called "ruling out" until you find the cause.
This machine has no power. I replaced the power supply thinking this would fix the problem. Still no power. Any other ideas? Could it be the MB?