I’ll just repeat what everyone else said. Some applications are able to crunch large data sets on GPUs with a small amount of memory because they can break the data up and process it in chunks; some can’t, and so they need the larger memory available from a Quadro or Tesla card because all of the data has to fit into the GPU’s memory at once.
So if you can break up the data, go with the GTX295. If not, go with the Tesla (or a Quadro, if you want the video output).
Go 4 Tesla ONLY IF you need that extra memory. TESLA is enterprise grade - more thoroughly tested and has ECC for memories, I believe.
Also I hope GTX 295 has the enhanced memory coalescing capability that TESLA series have. And, I hope they support “doubles” as well.
You may need to check the compute capability of both these cards. TESLA is 1.3 and supports “doubles” as well. What is the compute capability of GTX 295? If it is 1.3, it should be good enough.
If you dont need any of these features (now and in future), GTX 295 is the best option. They run faster than TESLA (more clock speed for shaders and memory) and they are priced less.
Thanks everyone, I’ve gone for tesla’s for now as I do need quite a bit of memory for some applications. I’ll be buying more later I think but I’m going to wait for fermi and see what the options are then…