Screen goes grey with black lines when gaming

[Carnifx]

So I recently installed an HD7950 in my rig and have been having issues with my display crashing. Sometimes when I'm gaming the screen goes grey with stripes but the machine doesnt power down. I seem to still have some audio as well. I installed speedfan and my GPU seems to sit around 50-60 degrees which I believe shouldn't be a problem.

One of the temp displays on speedfan called "Temp 2" changes back and forth from 127 to -55. I'm assuming theres just some error and its not actually displaying a real temp but is this any kind of issue?

So where do I start? I ran a test with HD Tune Pro and my drive is all good but whats the next step?

 

[Mace ya face]

Ignore Temp2. Remove overclocks, re-install drivers. If no luck check PSU. If still not working, GPU is faulty.

 

[Carnifx]

Ok thanks for the checklist. It isn't overclocked, I tried reinstalling the drivers with no luck. How do I "check" the PSU? I have a 650watt PSU.

 

[Mace ya face]

See if the PSU is a high enough wattage.