Annoying issue.

Good evening guys. A few months back i decided to build my 1st computer with the following components. An i3 3220,8gb ram,h77ma-g43 motherboard,xfx 550w core edition psu and an msi gtx 660 oc gpu.

For quite some time it has ran fine,but around 3 weeks ago i started to get a rather jarring issue when playing any kind of games and now even while just generally browsing. Basically every few minutes my screen will go crazy and start displaying red flickering horizontal lines. Does anyone have any idea on what this could be? I have a feeling it could be my gpu but without much knowledge in the area its hard to know.

Thanks for any and all help.