The Radeon R9 270X was 6% faster than the Radeon HD 7870 in DiRT 3 at 1920x1200 while it was 27% faster than the GTX 660 and 5% faster than the GTX 660 Ti. The Radeon R7 260X was just 4% faster than the Radeon HD 7790 but 23% faster than the GTX 650 Ti.
Again we see that the Radeon R9 270X is 6% faster than the Radeon HD 7870, this time in Far Cry 3. The Radeon R7 260X on the other hand was 11% faster than the Radeon HD 7790.