Intel Haswell Linux Performance Remains Mixed Against Windows

While Xonotic with low and high quality settings made Ubuntu 13.10 with the updated Mesa driver on par with Windows, that isn't the case when using the game's "ultra" quality settings. Xonotic with ultra quality OpenGL renderer settings yielded much better performance with Windows 8 than Linux.

GpuTest's GiMark and TessMark benchmarks aren't yet compatible with the Intel Mesa Linux graphics driver until its GLSL support is advanced.