Newly built PC turned on last night, now it won't. Help :(

Just as the title says. I was building my first PC, everything worked out fine last night. I had everything except the case fans working and when I pressed the power switch, everything worked and I could even see stuff on the display. This morning when I woke up to complete it, I hooked up the case fans, but this time it won't turn on. I tried unplugging all the cables that go into the motherboard and plugging them back in. I also tried to power it on by shorting out the power pins, so it's not the F-Panel connectors. Please Help

The only thing that I could say is take the PC apart and. Put it back together, make sure it is clean, all the pins are ok, nothing touching the pins. For the cpu besides the cpu. BEFORE doing that make sure that the PSU is not on a different voltage or something like that.

How did you turn it off? you didn't by chance turn if off by the switch on the power supply and forget to turn it back on?

Did you fix it?

Ya, know? I have done that and stressed myself out that my pc was broken.

For some reason after taking out the mobo and screwing it back in, it turns on again! Thanks for the response. Now I'm trying to overclock my fx-6300 to 4.2 ghz. Hopefully I won't come back with another post :P