The Radeon R9 290 graphics card still certainly has weird performance issues... The Radeon HD 6870 was running faster than the R9 290 on Linux with the Kaveri system when using the latest AMD Catalyst Linux driver. Additionally, all of NVIDIA's newer graphics cards were far ahead of the R9 290. The Radeon R9 290 is a $500 graphics card but was being outdone by a GeForce GTX 760 that can be found in the $250~300 price range. For this first test we see the GTX 680 / GTX 760 / GTX 770 hitting a wall on the performance limited by the APU while the Radeon GPUs were running far behind.
Unigine Heaven was unstable for the Radeon R9 290 with this latest Catalyst Linux driver. However, of the graphics cards that worked for running Unigine Heaven 4.0, the NVIDIA GPUs all ran much faster. There's still clearly some problems at hand with the Catalyst Linux graphics driver.
With Unigine Valley the R9 290 did work on the latest Catalyst binary driver and it was far ahead of the older Radeon HD 7850 and HD 6870 graphics cards. The GeForce GTX 760 though -- at almost half the price of the R9 290 -- was still faster when all GPUs were with their first Linux driver updates of 2014.