we’ve established that on-board memory is critical but the number of CUDA cores and their speed is also critical. The more CUDA cores (Stream Processors) your GPU has, the better. The faster they are, the faster your scenes will render. However, on the flip side the faster they are the more heat they generate. Here’s a comparison of CUDA cores & clock speeds on these three cards:
GTX 470 = 448 CUDA cores (core clock: 1215 MHz)
Quadro 5000 = 352 CUDA cores (unsure of clock information)
Tesla 2050 = 448 CUDA cores (core clock: 1150 MHz)
As you can see the “Gaming card†has the same amount of CUDA cores as the Tesla and they are clocked at a higher speed. This is reflected in the performance as well. When rendering with iray the GTX is noticeably faster than the Quadro 5000 and a little faster than the Tesla 2050 (provided I can fit the scene onto the GTX card).