GTX280 & GTX580

I have an Intel DP45SG main board equipped with a GTX280 graphic card that I used for GPU computing. I would add to this configuration a GTX580, and use them both separately and for multi-GPU programming. Can I do this ? Moreover, the nominal power consumptions for these cards are respectively 550W and 600W, can anyone suggest me a good power supply?
Thanks in advance

I don’t have any experience with the DP45G specifically, but in general there should be no problem running two different GeForce cards in the same computer. CUDA will list them as two separate devices, and you can pick which one to use with the cudaSetDevice() function. I currently run a GTX 295 in the same computer as two GTX 580 cards.

One thing to keep in mind is that the GTX 280 is compute capability 1.3 and the GTX 580 is compute capability 2.0, so you will either have to compile all your CUDA functions for compute capability 1.3 (which the driver will translate to run on either card) or you will need to find a way to load two different cubins, depending on the card capability.

As for the power requirements, I think you may have confused the recommended minimum power supply rating with the actual power draw from the card. A GTX 280 is rated to draw 236W, and a GTX 580 requires 244W. However, the CPU/Motherboard/RAM/disk drives/etc all require power as well (plus there are some efficiency losses), so NVIDIA specifies a minimum power supply rating of 550 or 600W. For your proposed setup with two cards, I think you will be fine with an 800W or higher power supply. I tend to buy Antec power supplies, but I don’t have any real evidence regarding the quality of different brands.