booting, No display or power Mouse/keyboard

[sebbeol]

Hello all!
I have a problem with my computer..
It have been working fine the yesterday, but today when I booted, No display or power in keyboard/Mouse.
Everything inside pc starts, light in cooler, motherboard, All fans, EXCEPT the system fan in the back of the computer. It spins when I boot, then stops. This have never been a problem. On the motherboard, on the display it says "15".
I have tried plugging out rams, and using a single at the time..
Setup is:
Motherboard : G1 sniper m5
Gpu : nvidia gtx 780
Cpu : i7 4770
Psu : corsair cs750m
Ram : corsair vengeance 2x8 gb

Any help or solutions? I am completely lost....
By the way, the computer doesnt reboot, it just stays on.

 

[alexoiu]

Hi, try clearing the CMOS (unplug the power cord and remove the CMOS battery for a minute).

 

[sebbeol]

I tired doing that.
Update - I tried removing the cpu, and booting. Still No display, and No power Mouse/keyboard. But the code Error "15" disappeared. It looks like a single pin is broken in the socket - But in doubt since I never opsende it...