Tom's hardware has a nice benchmark review of ATI's and Nvidia's current professional card lineup.
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It includes: ATI FireGL X2 ATI FireGL X1 ATI FireGL Z1 ATI FireGL T2 Nvidia QuadroFX 3000 Nvidia QuadroFX 2000 Nvidia QuadroFX 1000 Nvidia QuadroFX 500Sorry, no Quadro4 XGLs.
Quite interesting. Compared to the other benchmarks, the performance spread in the SWX benchmark is very small, indicating that the "value" cards are much better bang for buck in SWX.
The QuadroFX 3000 is the undisputed leader, but it certainly comes at a price.