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Old 2011-01-26, 00:46   #4
A Sunny Moo
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Aug 2007

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Originally Posted by Flatlander View Post
Cheap is good!
So I would be running 2 cards, one for cuda, one for the display? (The on-die GPU being disabled due to overclocking.)
You could do it that way, or you could just run the monitor off the CUDA card. I've heard that some CUDA apps will slow the graphics to a halt, but in my experience working with Gary's GTX 460, there doesn't seem to be a huge impact. (This may be because the applications being used, namely ppsieve and CUDALucas, were not as fully optimized as they could be, leaving enough "room" for the graphics to operate smoothly. I expect llrCUDA will behave similarly, though ppsieve/tpsieve would depend on how much they's been optimized since then.)

Note also that some BIOSes will turn off any GPUs that don't have a monitor plugged into them. (That's what Gary ran into--he was originally going to run the monitor off the integrated graphics.) This should be configurable somewhere in the BIOS, but it can be as confusing as all heck if you're not aware of it.

If you have a spare graphics card (doesn't have to be fancy) sitting around, you may as well use that to run the monitor and be sure that the graphics won't freeze no matter what crunching app you run. If you plan to do this, you should stay away from mobo #3--its x8 PCIe slot (the one you'd want to stick the monitor's graphics card into) shares its bandwidth with the x16 slot, so running cards in both would impact the performance of the crunching GPU.

Last fiddled with by mdettweiler on 2011-01-26 at 00:50
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