Looking Back: ATI's Catalyst Drivers Exposed

Halo

Halo represents both a curse and a blessing among possible titles to benchmark. As one of the first FPSs to make good use of SM 2.0 and a very popular title on both the PC and Xbox, it's an important title to use to see what ATI could do with the newest feature of the 9700 Pro; but at the same time, it was still a console port that was in many ways mediocre. While we would have liked to test Gearbox's "Custom Edition" that implements properly optimized shaders, the lack of single player support in that version has limited us to the less optimized original version of the game. The lack of AA support has also limited us to only benchmarking Halo without any advanced features turned on.

First of all, the 0 next to the Catalyst 3.00 drivers is not a typo; with the 3.00 drivers, Halo suffers from a massive stuttering problem that caused the time demo to play at unequal speeds and otherwise returned senseless benchmark results, and was excluded as a result. Beginning with the 3.04 drivers then, we see Halo receive a significant performance boost late in to the life of the 9700 Pro, rather than in the beginning where we'd expect it. ATI has attributed this to z-buffer optimizations in their driver for dealing with this game; this optimization was good for a nearly a whopping 25% improvement in performance, and it's a shame that ATI didn't do this earlier. Otherwise, we see a drop off between the 3.04 and 3.06 drivers, and then a slow increase of 10% through the 5.05 drivers; the drop off is not significant at less than 11%, but it's still noteworthy that the game actually got a bit slower before its release around the time of the 3.06 drivers.

Catalyst 4.02 versus 3.09 (mouse over to see 3.09)

Looking at the screenshots, there is a very noticeable IQ difference, but not one that correlates between any of the performance changes. The above is a comparison between the Catalyst 3.09 drivers and the 4.02 drivers, with a focus on the flashlight. With the 3.09 drivers, the light has a very noticeable hard edge, while this becomes a soft edge under the 4.02 drivers. This is something that we mentioned previously in our Fall 2003 IQ Analysis, where with the 3.09 drivers, our 9800 Pro was doing hard edges while NVIDIA's 5900 was doing the proper and more complex soft edges. ATI fixed this problem after the 3.09 drivers - the flashlight was working correctly without a performance hit. While we'll never know if it was a bug or an intentional way to improve frame rates (as ATI never mentioned this in any of their release notes), it's good to know that they could get it right without a performance hit.

As all the other pre-3.09 shots are indistinguishable from our 3.09 shot, and all post-4.02 shots are just like our 4.02 shot, there appears to be no other IQ change other than the flashlight fix. Overall, Halo stands apart as a game that received a constant (if small) improvement in performance, and the second game to receive an IQ-related fix.