MOST OF YOU ARE probably familiar by now with the controversy surrounding the current drivers for ATI's Radeon 8500 card. It's become quite clear, thanks to this article at the HardOCP, that ATI is "optimizing" for better performance in Quake III Arena—and, most importantly, for the Quake III timedemo benchmarks that hardware review sites like us use to evaluate 3D cards. Kyle Bennett at the HardOCP found that replacing every instance of "quake" with "quack" in the Quake III executable changed the Radeon 8500's performance in the game substantially.

The folks at 3DCenter.de followed Kyle's trail and discovered that, on the Radeon 8500, "Quack 3" produces much better image quality—texture quality in particular—than Quake III. The FiringSquad observed the same behavoir, only they did so in English.

With the publication of these articles, it became a matter of public record that ATI was intentionally sacrificing image quality in Quake III for better benchmark scores. The issue, as far as I was concerned, was settled: ATI was busted.

But one question remained: How exactly did they implement their cheat? Now we have an answer. Read on to learn the secrets of ATI's drivers.