Im thinking of putting a 4xGTX295 machine. I’ve tested a quad core with 2 GTX295 and it seems ok for now.
What I was told that in order to have 4 PCI lines to host 4 GTX295, I can only use one CPU quad core, therefore
each core will have to handle two GPUs (or one dual GTX).
Has anyone tried this ? what do you think? I guess it would have been better to have one core per gpu but…
Also, has anyone tested the new GTX285? how is it compared to the GTX280 or GTX295?
Actually, this depends significantly on kernels. If you’re firing hundreds of kernel invocations per second (i.e. each kernel takes only few milliseconds) then high load in background processes is a problem. You will also likely to see performance degradation if #CPUs < #GPUs in this case.
If your kernels run for longer time, i.e. for second or so, you can play with CU_CTX_SCHED_YIELD flag and it will likely help you to avoid performance degradation.