Computer with the black screen

I was playing a game called Watchdogs 2 and my computer made a loud hrmm sound and started trying to repair itself several times over and over. I turned the computer off and thought it may need to get a fresh boot and after turning it off and on I get nothing but a black screen. I have two of the same builds. My computer and my wifes computer with very similar setups. We have the

Maximus Xiii Hero mother board
4gb rams x4
GTX 980 Ti graphic cards
HX 850i power supplies

I have changed out the video card and it didn't change anything
I have changed out the power supply and it didn't change anything
I checked all my connections inside the tower and didn't find anything
I have had this setup for a little over a year with no issues
I'm stumped on what I should check next because checking the mother board via changing them out doesn't seem fessible because I don't have any thermal paste
If you have any suggestions on what I could try next please suggest it.
Thanks in advance for any advice