Gpu issue

I just bought a new gpu (evga SC 780) and a new psu (haleV2 700w). After hooking everything back up I ran a few benchmarks and noticed that I had a strange screen issue whenever I launched a game. It looks like I have a bad chord but it only does it during gaming. Vsync fixed it for a little while but now it's back. Any help is appreciated.

-thanks 

Bad chord what like a E flat dim7'th? Have nfi what you are trying to describe champ. Are you able to take a screenshot?

Either way double check all your connections, pcie slot included. Reinstall drivers etc. Try gpu in anther pc even.