30-4-2011 22:38:01 NVIDIA GPU 0: GeForce GTX 570 (driver version 27061, CUDA version 4000, compute capability 2.0, 1217MB, 1509 GFLOPS peak)

Running smoothly, however card is atm heavy underclocked because of heatissues. 2 Extra casefans should solve this in the near future.

Win7 X64 Home Premium SP1, 8-core Intel i7-2600 @ 3.40 Ghz, 4GB DDR3, MSI P67A-C43

2 x GTX 570 getting throttled occasionally when OCed. ALWAYS gets throttled when boinc switches from GPUGRID to PrimeGrid...not the other way around though...interesting. Would cut the clocks by over 50%. Reboot and they'd come back up.

Tried taking the cards back to the reference clocks and the same thing would happen, immediately after switch from GPUGRID to PG.

Nvidia set to "prefer maximum performance" - still happened, all the time. This was not an intermittent problem, could be duplicated at will. Removed the 270.61 driver and reinstalled 266.58, no more problem, even when OCed. Obviously something is up with this driver and I won't be using it any time soon.

Al

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You will probably find that prime grid runs with higher GPU utilization and has higher power requirements. Like some performance tests this forces the card to run too hot/use too much power and so the latest driver forces the card to down-clock. If you had a power meter you could test this at the wall with 266.58.

Perhaps the mechanism is more heuristic with the 270.61 driver, or NVidia have just added a PG exception to their throttle list.
If you only crunched for GPUGrid this would not be a problem, for now anyway.

Given the architecture I would have expected this to be more of a 500series feature, than Fermi-wide, but MarkJ reported similar findings on a GTX480 running Seti.

Anyone seeing this throttling with MW or another project?

- Well it didn't last, the 270.61 WHQL driver seemed to work for a few days but it started down clocking my Windows XP x86 systems GTX470. It then just stayed low, either 405MHz or right down to 50MHz, and no application I tried would get it to increase the clocks. Closing and opening Boinc and even system restarts did nothing to reset it. At 50MHz it was causing system instability and probably damaging the card. Apparently WHQL now means world wide beta test.

I suspect whatever updates are in the driver it allows it to check which processes cause the card to overheat/use too much power and then logs them some how and prevents them from using the GPU properly ever again. Maybe that update component is doing more than just checking for standard driver updates.

Anyway, I'm recommending that people stay away from 270.61.

I was actually on a 30 day mission to test my overclocked 570's using PG as the test. I've been fighting the heat since day one, but everything seems stable now. The 2 - 570's are now on GPUGrid full time. PG has been relegated to an old computer with a gt430. I'm still afraid of the new driver and will not be upgrading until GPUGrid requires it..

Al

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