Windows 7 graphical glitches

[Tantalus]

Cannot explain so sending screeny.

To accompany that on occasions my monitor flashes off and on.

I first thought it was to do with the GPU drivers but looking at google it appears to be a tell-tale sign of near PSU failure.

This only happens in Windows 7, not Vista, so that leads me to believe it is drivers.

Could someone give some guidance?

Cheers.