System will not send input to monitor

[Raiins]

Out of the blue my (almost) 2 year old PC won't display to my monitor. I know the monitor works because I hooked another pc up to it so that is not the issue. Also tried a different gpu and psu (same problem) and have tried switching around the ram. I have reseated the entire pic twice now and have cleared the cmos a few times. The pc also shuts off during startup once and only once then goes about its business but will not post.
Note: the issue started when my pc was restarting after updating windows and my motherboard utility called app center at the same time.
Specs: CPU intel i7 5820k
GPU nvidia gtx 980ti
MOBO Gigabyte Ga x99 sli
RAM DDR4 corsair 16gb
I suspect bad motherboard but I don't know at this point

 

[maz89]

Definitely sounds like it's the mobo, since you've already run isolated tests on all your other components (graphics card, PSU). When you remove RAM, does the mobo make any beeps (assuming case speaker is attached)?