AMD Radeon R9 270X On Linux
For the open-source OpenArena 0.8.8 game at a 2560 x 1600 resolution, the Radeon R9 270X came in 16% faster than the Radeon HD 7850. The R9 270X at $200 was obviously much slower than the GeForce GTX 680 and Radeon HD 7950.
When running Unigine Heaven 4.0, the Radeon R9 270X was 52% faster than the Radeon HD 6950 on Linux. The Radeon HD 7950 was 20% faster than the R9 270X graphics card.
For being a $200 graphics card, the Radeon R9 270X performs strongly against the graphics cards we were able to compare it against to.