Computer shuts down after 1 second of power on

[Jeatu]

Hi. I'm new here, and my problem has probably already been discussed on another thread, but I just kind of didn't want to have to read through every thread.
Ok, I came home from work, and my PC was shut down. I tried to start it up again, and it powered up, but for literally only a second, then shuts down. I've opened it up, and checked to see if anything was touching the motherboard, or if the heatsink was not making proper contact with the CPU. Everything looked fine visually. I did notice that when I unplug the P8 connector the optical drives start up, but nothing else (that's probably normal, but I've never seen it). The power supply, I suspect, is fine since the fans and everything start up for just literall one second. Anyone know what's going on? Am I forgetting to check something? Anything would be helpful. Thanks.

 

[ComputerFail]

How far do you get when you start up?
Do you get through to the windows loading screen?
Do you get the BIOS shortcut F2 option?

 

[SNGX1275]

Hi. I'm new here, and my problem has probably already been discussed on another thread, but I just kind of didn't want to have to read through every thread.

Thats unfortunate.

The power supply, I suspect, is fine since the fans and everything start up for just literall one second.

That is a symptom that is observed with some power supply failures. In fact, the only PSU failures I've personally observed displayed that behavior, although I've only observed 2.

 

[Jeatu]

How far do you get when you start up?
Do you get through to the windows loading screen?
Do you get the BIOS shortcut F2 option?

Actually, I'm on it now, and it seems to be running fine, but it took a bit for it to start up. Last night, however, it didn't get anywhere. The fans would start up, but then it would shut down. I have a feeling I may run into this problem again.