I'm looking to add a bit more crunching power to the computer that has been getting most of my BOINC credit, and the most obvious solution seems to be to add a second GPU.

Right now I'm using a FirePro v7800 (similar to Radeon 5850), which is out of my price range to add a second, so Crossfire Pro is not really what I'm looking for. I do, however, have two PCI Express 2.0 (or 2.1, I forget) x16 slots, and an 850W power supply with plenty of connectors.

My question is: what do I have to do to add a second GPU? If i just drop in a second card will BOINC detect it just fine and start using it? Can I run one AMD card and one nVidia card? Can I run work for different projects on each card concurrently? Any other problems to look out for?

As a side note, while I'm not looking to do a Crossfire or SLI setup right now I may later, and perhaps someone else reading this will be. How does BOINC react to that? I've heard that BOINC doesn't see a set of GPUs in SLI/Crossfire as a sinle GPU, but will it see each individual one still? What about the single PCB, dual GPU cards, like Radeon 6990 or coming GTX 590? Any other considerations?

Thanks in advance!

I don't know if this link to a different thread helps but I thought I would post it here just in case you or someone else is interested.

http://boinc.berkeley.edu/dev/forum_thread.php?id=6484

My question is: what do I have to do to add a second GPU? If i just drop in a second card will BOINC detect it just fine and start using it?

BOINC will by default only use the best card and not use any others. You have to tell it to use the other or others. See "OK, so now I disabled SLI and BOINC only recognizes one video card. What is up with that then?" in my FAQ, which will explain how to do that. (That part of the FAQ is old...)

Can I run one AMD card and one nVidia card?

Yes.

Can I run work for different projects on each card concurrently?

Yes. Although not continuously, work done on the GPU will switch as it's done on the CPU. Unless, of course, you have one project specifically using the AMD only and another project using the Nvidia only.

Any other problems to look out for?

When in doubt, or trouble, ask. Either here or at the project forums.

As a side note, while I'm not looking to do a Crossfire or SLI setup right now I may later, and perhaps someone else reading this will be. How does BOINC react to that?

Earlier BOINC versions didn't see individual cards when SLI was used, they saw one GPU only. Later versions (6.6 and upwards) fixed that. So even with SLI on all GPUs are detected individually.

What about the single PCB, dual GPU cards, like Radeon 6990 or coming GTX 590?

Same thing as with SLI. Single card, multi GPU will be seen as multiple GPUs.

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