Desktop keeps turning itself off. PSU, GPU or something else??

[bigben]

Hiya,

My desktop keeps on turning itself off for some reason. Cause isn't very obvious, sometimes it happens when just listening to music or browsing internet, so not demanding stuff.
Insides are very well dusted and airflow is fine. Everything is properly seated into their slots. I tried taking out one of the GPUs and so far (1 hour later) it hasn't had any problems, although this could well be coincidence.
The PSU is only 5 months old.

Does anybody have any ideas what's wrong?

Thanks

 

[steaky360]

Does it just switch off or does it shut down? I'm guessing it just switches off. Try swapping out the GPU's to see if it starts again with the other one plugged in.

 

[bigben]

Just switches off, no warnings. I'll leave it another half hour and then I'll swap them over.

 

[bigben]

Left it on all morning with just the other graphics card in and no problems.
Maybe I'll leave one of them out for a week or so and see if I have the problem again.

 

[bigben]

Update:
Had it switch itself off again just now, had GPU 1 in it. I've swapped out the graphics cards again so if I get the issue again. If I get the problem again I'll have to start looking elsewhere.