Image Quality Performance
The image quality performance graph offers up the first interesting insight into the performance of the PRO. If you compare the graph above with that of the X800 XT, here, you can see the PRO suffers more when 6X AA is enabled.
The drop-off in performance, steeper than the XT's equivalent graph, is, in this case, down to memory bandwidth limitations. Increasing the memory clock in UT2003, with 6X AA applied, gives a near linear performance increase, until you cease to be bandwidth limited again (which happens quite quickly).