I'm planning to buy a serious GPU for running a parallel algorithm on (budget 2k-4k). Now I see everywhere supercomputers featuring nVidia Tesla GPU cards "made especially for GPGPU".
While this seems very nice on first sight, a better reading makes me have serious second thoughts on that: compared to e.g. a Radeon HD 7970, its performance (in terms of flops) is significantly lower, its cost price is significantly higher, and I can't seem to find any benchmark comparison between the Tesla and normal gaming GPUs.
I have found that the Tesla features ECC-memory. Is this the only difference? Or am I missing a deeper architectural difference between both? Perhaps relevant info: I will be using OpenCL, not Cuda.