X-bit labs

ATI RADEON X1600 XT: Mainstream Performance Redefined Once Again? (page 19)

Category: Video

by Alexey Stepin , Yaroslav Lyssenko, Anton Shilov

[ 10/07/2005 | 06:19 PM ]

Performance in Synthetic Benchmarks

Futuremark 3DMark03 build 360

Even though 3DMark03 benchmarking suite doesn’t really like RADEON X800 and RADEON X1000 architectures, our today’s hero managed to show some worthy results in the total score chart: over 9,000 points. Its most evident competitor, GeForce 6800, turned out 341 points behind. Now let’s take a closer look at each gaming benchmark separately to see what determined the newcomer’s victory here.

The failure in Game 1 test is not surprising to me: it uses fixed TnL functions, in particular point sprites, and requires high fillrate. Here I would like to make some comments: although the background is created with large polygons covered with a single texture, all aircrafts are rendered with 4 textures. We already know that RADEON family has some problems with TnL emulation, which emerge from CATALYST driver issues. Therefore, it is quite logical that RADEON X1600 XT turned out the last but one in 3DMark03 Game 1 test. The only one slower than our today’s hero is RADEON X700 PRO suffering from cut-down texture caches. However, it still outperforms RADEON X1600 XT in 1600x1200 with enabled full-screen anti-aliasing.

The newcomer feels much better in Game 2 test and outperforms GeForce 6800 in 1024x768 (which is the default resolution in 3DMark03). As the resolution increases, RADEON X1600 XT and GeForce 6800 level out and the situation remains like that until the end of the test. This benchmark is very sensitive to the GPU’s ability to efficiently process the Z-buffer, and RADEON X1600 XT is pretty good at it. Firstly, it features 8 Z-Compare units and hence can process twice as many Z values per clock cycle. And secondly, RADEON X1000 architecture can compress Z-buffer data as 8:1. Of course, high GPU frequency also contributed to the success of RADEON X1600 XT. All these factors together allowed the new ATI solution to come out on top in Game 2 test.