AMD Gallium3D & Catalyst Drivers Compete Against Windows
The Unvanquished game results were mixed with its OpenGL 3 renderer with the Radeon HD 6770 performing best on the Linux Catalyst driver over the Windows driver, which was also the same for the Radeon HD 6870. However, the Radeon HD 7850 graphics card ended up being much faster on Windows over Linux.
Xonotic is favoring the Windows Catalyst driver over Linux. The Radeon Gallium3D driver is much slower than Catalyst for this rather demanding open-source game.