GPU or PSU going to up-lorry?

[asuna88]

Hi guys, some background info about my rig -

Abit IP-35e motherboard
Kingston HyperX 800 2 x 2gb RAM
Intel Core 2 Quad Q6600 2.4ghz
WD Caviar Green 500gb

Cooler Master Real Power Pro 550w (~6 years old)
XFX GTS 250 (~5 years old)

So recently I was playing Hearthstone when suddenly my display flickered and freezed - had to do a hard reset.

Since then, whenever I launch any 3D intensive application, the display driver would crash "display driver stopped responding and has recovered". I thought it was a driver issue so I tried out several older drivers (which were fine in the past) - still the same issue.

Ran Furmark to confirm and always crashed around the 69C - 70C point. I doubt its a temperature issue as my card always ran 70C and above during gaming without any problem.

I'm suspecting either my PSU, or the card itself is going to up-lorry soon. Been getting screen flickers now and then, and random black squares.

Any advice? Or anything I can do to narrow down the culprit?

 

[royfrosty]

If you mentioning black squares already as good as GPU going to up lorry already.