Why isn'y my pc starting up?

[Bricks1226]

I just plugged all of my wires into all of the correct place on my motherboard. But, the fans and everything won't start up. The light on my GPU turns on but when I press the power button on the front of my case, my pc won't turn on. For specs on my pc just ask please.

 

[ss202sl]

http://www.tomshardware.com/forum/261145-31-perform-steps-posting-post-boot-video-problems