Radeon OpenGL Benchmarks On Fedora 22
With the very basic OpenArena test case, the R9 270X performance surprisingly dropped on Fedora 22 while the R9 290 inched slightly ahead.
Xonotic with low image quality settings didn't see much difference...
Xonotic with high image quality settings saw roughly the same performance for the R9 290 between the updated Fedora 21 installation and the stock Fedora 22, which was ahead of Fedora 21's out-of-the-box configuration. However, like with OpenArena, the R9 270X performance had regressed on Fedora 22.