Quick backstory:
 
I bought a GTX 670 in 2012, it started giving me black screen flickering in 2014 and had it RMA'ed. I was sent a 770. Well, now my GTX 770 is getting a ton of black screen flickering when playing games. I checked my monitor and cable and everything seems fine with those two components. I suspect my GTX 770 is the cause of the flickering. Is there anything I can do to be certain?

Edit: I should add that I already checked my BIOs per a friend's suggestion and the +12v rails are reading at 12.38.

I had the same issue off and on at random times can make a list of fixes and work your way down like I did and have not had any issues now.
 
1:make sure you have the latest nvidia driver :I even went as far as to uninstall and reinstall a fresh copy of the latest driver myself.
2:use some kind of monitoring software to keep track of temps while gaming like evga precision, speccy ,etc. and see if some numbers are out of normal range.
3:reseed the graphics card (take it out and install back in) making sure no dust got between the contact points. (sounds stupid but I had 1 computer do that with the memory) would not hurt to do the memory as well.
 
side note: posting full system specs would be helpfull with troubleshooting software/hardware issues.
 
hope this helps.