Is there something wrong with my GTX260s?

[RAMChYLD]

I've swapped them out for GTS450s, but I'm still puzzled about this.

I had a pair of GTX260 card, model Asus ENGTX260s/HTDI/896M.

After the box has been running for some time (say, about 4 hours), they'd become unstable. The screen would go black and fill up with random green patterns. Upon attempting to reboot, the machine might either boot into gibberish-filled screen and hang, or be stuck in a POST loop (blank screen with a beep every 5 seconds or so). If I let it sit unplugged for half an hour or so, it then becomes usable again.

I checked with the shop I bought the cards from and they told me it's heat damage. But I'm using a Xigmatek UtGard case with all optional fan slots loaded and the ventilation worked out on paper, plus the rig sits right in front of an air conditioner, so it seems unlikely.

Another possibility I've gotten from a friend is that the PSU is not powerful enough. But then I'm using a CoolerMaster 850w PSU, which I believe is plenty. I've noted, tho, that the PSU would click when I power up my rig with the 260s installed. It doesn't do that with the 450s. But I just thought it normal since I have two other PSUs that clicked when powered up, an Acbel 750w in my secondary gaming rig and a Enermax 620w in my MCPC, and both machines are stable.

Any ideas what else I should check and if the cards are actually alright? I don't want to RMA them given that Asus' support is pretty bad in Malaysia and wants me to RMA through the store I bought the cards from. And the last time I RMAed a something through a store (it was a Soltek motherboard, but I was told to do the same thing), I've never seen said part ever again.

850w should be more than enough. Have you tried each card individually? The symptoms sound like bad ram on one of the 260s to me.

[Redeemed]

Originally Posted by grey_1

850w should be more than enough. Have you tried each card individually? The symptoms sound like bad ram on one of the 260s to me.

This here.

Try them one at a time. See if one card works excellent and the other not? This is the likely culprit.

[RAMChYLD]

Boot only one? Sounds like a plan. I'll try it the next time I have time to mess with them. The replacement 450s work wonderfully but I plan to build another rig sometime next year, and plan to reuse the 260s then. So I'll probably mess around with them cards at that time.