AMD Kaveri: Catalyst vs. RadeonSI Gallium3D On Linux

First up was the very old OpenArena 0.8.5 game that's a very basic GL2 game and not really demanding with modern GPUs, especially when using the proprietary drivers. The best-case open-source configuration at the time (Linux 3.16 with Mesa 10.3) left the A10-7800 with Radeon R7 Graphics running about half the speed of the Catalyst driver. While the open-source driver has a ways to go, its performance was over three times faster than the code shipped in Ubuntu 14.04 by default. Both the kernel and Mesa upgrades brought significant performance improvements for the Kaveri APU graphics.

With the newer OpenArena release that's more demanding, since the time of the Ubuntu 14.04 LTS release the open-source RadeonSI performance is almost six times faster when switching to Linux 3.16 with Mesa 10.3.

Tesseract wouldn't even run on Mesa 10.1 as shipped in Ubuntu 14.04, but now with the latest open-source Radeon GCN graphics driver code the AMD A10-7800 performance was about 59% the speed of Catalyst.