Radeon HD 7950 vs. GeForce GTX 680 On Linux

The overclocked Radeon HD 7950 configuration (900/1375MHz vs. 800/1250MHz) led to around 10% better performance with Unigine Sanctuary at 2560 x 1600. This overclocking allowed the HD 7950 to run at the same speed as the stock GTX 680.

This also allowed the HD 7950 to have a narrow advantage when it came to performance-per-Watt

The GeForce GTX 680 was around 7°C warmer than the Radeon HD 7950 and going through around 30 Watts more of power.