Newly built PC, won't start now.

[The Memento]

So I just finished my first build and everything was fine. I have my OS installed and everything. I decided to do some cable management and close the case. I then pressed the power switch and nothing happened.

I open the case to try and pinpoint the issue. Everything seems to be in place. The "power" symbol is illuminated on the mobo when it is plugged in. But when I press the power button on the computer nothing happens.

Anything else I can do?

 

[Deemo13]

Make sure the power button connectors are connected to the motherboard.