ATI R300 Mesa, Gallium3D Compared To Catalyst

Starting with OpenArena its ATI R300 Linux performance results were interesting for several reasons. While the ATI Mobility Radeon X300 was introduced many years back, the very latest open-source Radeon drivers both with the classic Mesa driver and with the newer Gallium3D driver was no comparison to the Catalyst driver from two years ago. Interestingly, the classic Mesa 7.2 R300 driver from two years ago was twice as fast as the current Mesa 7.9-devel. This is similar to our recent article showing how an old Pentium 4 system runs Ubuntu Linux where the ATI Radeon 9200PRO (R200-based) graphics card was slower with the modern code-base. This slowdown is likely due to the DRI2 support that is found along the KMS code-paths (as confirmed by AMD's Alex Deucher post137352) and is used by default with modern desktop Linux distributions. Finally yet importantly, the newer Gallium3D driver was actually slower than the classic driver with the Mobility Radeon X300.

With World of Padman, the very latest Mesa 7.9-devel code via both the classic and Gallium3D drivers is actually faster than the Catalyst numbers from two years ago! Albeit this ioquake3 game was not playable with either Mesa or Catalyst, but the open-source drivers do offer a higher frame-rate. The Mesa driver from two years ago also could not properly run this test without locking up. While the ATI Gallium3D driver has been running faster than the classic driver has in many tests we have conducted with more recent Radeon hardware, with the mobile RV370 GPU there does not seem to be much of a performance difference.

When running Tremulous, the Catalyst driver returned to running significantly faster than the Mesa 7.9-devel drivers: 69 vs. 12~14 FPS. The open-source Radeon 3D driver stack found in Ubuntu 8.10 by default was also much faster than what ATI customers can currently experience in a modern Linux distribution with the KMS/DRI2 defaults.