Simultaneous CPU/GPU stress testing

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OK, so I thought I'd use Furmark to get my max GPU clocks. Did so, got temps around 95C. Wondered what they'd go up to with P95 also running... So left both Furmark and P95 running simultaneously for an hour. GPU got to 100C, but no artifacts so I'm OK with that. BUT P95 failed on 2 threads - I have recently tested this same CPU overclock and it was 24+ hours stable on it's own. Interesting I thought, will add more CPU volts and try again. From now on, my final stability check will be simultaneous P95/Furmark testing. The PC must be working hard as the PSU fan is really loud, something I've never heard before.
 
Soldato
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hmm.. Not tried that combination, but I've not used prime95 or orthos much. I tend to use Linx and Intelburntest V2 for ram/cpu testing as well as OCCT. OCCT have numerous benching options including one for psu stress testing, gpu and linkpack.
 
Soldato
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My guess would be that the increased strain on the system caused by the GPU load is causing more vdroop on the motherboard due to the increased power usage. Keep an eye on what actual volts are as the GPU goes under load, as if they drop too low than that may well be the issue.
 
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My guess would be that the increased strain on the system caused by the GPU load is causing more vdroop on the motherboard due to the increased power usage. Keep an eye on what actual volts are as the GPU goes under load, as if they drop too low than that may well be the issue.

Yeah that was basically what I was thinking, gonna leave it running all night with a bit more CPU volts chewing through off peak power...
 
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You must be getting close to the limits of that Corsair 520w with that rig. That will be why the psu fan is working so hard. Could be throwing a bit of instability into the rig.

Cannot get stable when running both, even bumping the CPU volts miles up. Pretty certain it is the PSU now given how loud the fan is going... Anyway, will find out soon as have ordered an HX850.
 
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Well, I'm seriously impressed (and a bit confused...). Installed the HX850, and my max CPU temp whilst P95 testing (nothing else changed, including CPU volts) has dropped a scarcely believable 12C. So I've upped the O/C, dropped the volts and it appears to be P95 stable (testing as I type, and still 10C cooler than the lower O/C!). Didn't realise quite how critical the PSU is and how much difference it can make. Excellent.
 
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