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Message boards : Number crunching : Unfavourable Tasks when running multiple (2) GPUs

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Message 131381 - Posted: 22 Jul 2019 | 19:19:48 UTC

I have a Windows 10 64 PC and 2 GPUs.

Just recently I received 2 large tasks which is fine but there is a problem.

For some reason these 2 tasks do not play good with TThrottle.

I can run each independently and the Throttle is 50% with nothing running on the second GPU.

When I run both together or even one with a Collatz GPU task then the Throttle goes up to 99% very quickly.

In other projects I can comfortably run 2 GPU tasks without any issue.

I think there must be something special in the way these tasks run on windows that causes Throttle to misbehave.

I did inquire to the author about Throttle and 2 GPUs and within his reply he said,

"As it can't throttle the actual GPU it slows down the feeder CPU process."

Does anyone have a workaround for this. I Use Nvidia 980 cards.

Primegrid is not a new project and I find it hard to believe this is a new problem but after reading through the forum I could not find anything that helped.

I am happy to support but do lack a little in the expertise ;)


Here is the example of the 2 tasks,

Here is the image showing when 1 (large) Primegrid task runs the Throttle is 50% (it is the same, 50% Throttle, when I choose either of the Primegrid tasks shown in the first image).

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Message 131403 - Posted: 23 Jul 2019 | 10:27:46 UTC

What throttling temp did you set on the GPU? Seems it's quite low if it's already kicking in at <70C. These higher n GFN tasks are very demanding on the GPU, so it will be considerably hotter than with a lot of other projects. And of course more so if you have two cards in the same system.
Long live the sievers.

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Message boards : Number crunching : Unfavourable Tasks when running multiple (2) GPUs

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