Different speeds on identical GPU's.


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Miklos M.

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Message 1509262 - Posted: 27 Apr 2014, 18:23:46 UTC

Could anyone tell me why on my computer, where I have two NVIDIA GTX 780ti's one (designated according to my computer as 1 is running much slower than the one designated as 0?

Thanks.
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Message 1509280 - Posted: 27 Apr 2014, 19:35:59 UTC

With only 3 tasks complete to look at it is hard to tell. One has 42.89% blanking. So isn't good to compare at all. The other two are 0% & 2.59% blanked. So better to compare, but only having one data point for each card doesn't give much insight.
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Message 1509283 - Posted: 27 Apr 2014, 19:45:16 UTC
Last modified: 27 Apr 2014, 19:49:05 UTC

Do you have enought cores free to keep both GPU`s well feeded?

Another thing you need to see is the GPU usage and if for any reason your GPU slowdown the clock.

But i agree with HAL 3 WU is too few to tell something concrete.
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Message 1509284 - Posted: 27 Apr 2014, 19:52:00 UTC
Last modified: 27 Apr 2014, 19:53:38 UTC

From what I see, you are using AstroPulse r1843 with driver 335.23. The CPU times are way too low. First guess would be you don't have 2 free CPU cores feeding the CPUs. Those are terrible times for a 780, with too low CPU usage for r1843.
Try freeing at least 2 CPU cores...

Is there an echo in here?
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Message 1509300 - Posted: 27 Apr 2014, 20:39:48 UTC

For my 780 SLI and i5 2500k system I:

Installed the lunatics optimized apps for GPU AP and GPU v7

I did NOT install the CPU versions.

I run two work units per card.

Its important to leave 1 CPU core free for each GPU work unit. So with my quad core I don't do any CPU only tasks.
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Message boards : Number crunching : Different speeds on identical GPU's.


 
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