CUDA bottleneck question

allangr

Distinguished
Aug 24, 2010
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My setup:

2 - 8800GT running the latest Nvidia drivers

One video card is set for video, the other is set for Phys-x

under this config I can run 2 instances of SETI@Home ( CUDA ) and both cards will max out the CUDA processers and the math will fly. Takes about 5 mins to process each SETI@Home work load.

But, if I take the same setup, and do nothing but turn on SLI mode, the 2 instances of SETI@Home ( CUDA ) basically crawl and the video cards seem to just idle. Takes over an hour to process each SETI@Home work load.

As well, if I leave the setup in SLI mode, BUT only run one (1) SETI@Home ( CUDA ) process, it flys again and takes 5 mins.

Any comments?
 

MrBig55

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Jun 27, 2011
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Oh well it could be due to a poorly optimized graphic driver (do update it to the latest) or a poorly optimized software (seti may not be able to support SLI).

Anyways I always found that seti is a waste of time, I prefer the use of Folding@home since this one helps medicine.