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So I am running a 12 core Xeon with 24Gb my GPUs are GTX580 x2, with 3GB each. I also have a Quadro 4000 with 2GB of ram. The answer depends on if NV is using GPUs separately or together. Lets say if it is using them together and I want to run 4 cores plus two GPUs then I would have to allocate 50% ...

Do I then divide the memory for the total memory of all of the GPUs or still for each one individually?