My Computer turns on monitor comes on but shows not picture

[bah11]

I can see the computer come on, but the monitor turns on and shows no picture, but keyboard/mouse do not turn on I think the mobo is dead I am very unsure. So, I opened up my computer and reseated everything. And still nothing, I'm not sure what to do. On this issue. The computer was working fine till now. i have no clue on what to do or how to fix it.
My build is:
Mobo: 990FXA-UD3
Processer: AMD FX 8-Core( 8120)
GPU: EVGA GTX 560 TI
Power: 910 wats Silencer
Ram: 16Gs of Ripjaws ram

[techsheaven]

Is it on-board video (part of the main board), or off-board video (plugged into an expansion slot)? If you have both, try each; if neither works, remove the off-board video card, and plug your monitor into the integrated VGA port.

Let us know what you find out, and we will continue troubleshooting.