The Radeon HD 7970 GHz Edition was 10% faster than the standard 7970 at 2560x1600 when testing with DiRT 3 as it averaged 68fps. Despite that gain it was still 6% slower than the GeForce GTX 670 and 11% slower than the GTX 680.
DiRT Showdown is the world’s first game to use Global Illumination while it also supports Advanced Lighting via Forward+ Rendering, High Definition Ambient Occulation (HDAO) and Contact Hardening Shadows. Global Illumination is a group of algorithms that are used to add more realistic lighting as they not only take into account light that comes directly from the light source (direct illumination), but also other light which is reflected from other surfaces (indirect illumination). By combining the two you get Global Illumination and DiRT 3 Showdown looks very impressive when using this technology. Using the maximum in-game quality settings, which includes the use of Global Illumination, we found that the Radeon HD 7970 GHz Edition as capable of rendering 67fps making it the fastest graphics card tested. It was 6% faster than a standard 7970 and a whopping 52% faster than the GeForce GTX 680.