Monitor starts flickering and green screening, not sure why.

[xshanex2010]

After about 30-60 minutes my screen starts flashing in and out from a solid green screen to the normal screen and doesn't stop till I reset it. Iv tested the ram via memtest86 with no errors. I thought it might be the graphics card so I just replaced it via RMA, but with the "new" card I'm still having the same issue. The computer isn't crashing and the card isn't over heating. I'm not sure what's causing this issue, any ideas?
OS- windows 10
Graphics- sapphire r9 390
Ram- 20gb
Mobo- MSI z97-g45
Power-corsair 750w
Ssd-500gb Samsung 850evo

 

[CountMike]

It leaves PSU as most likely culprit than.