Left 4 Dead is a fan favorite that uses the Source engine supporting DirectX 9. Testing with maximum in-game quality settings along with 8xAA/16xAF, the Radeon HD 5970 was able to achieve an average frame rate of 114fps at 2560x1600. This meant that the Radeon HD 5970 was 39% faster than the GeForce GTX 295 and 52% faster than the Radeon HD 5870.

The very latest game to be included in our review, Left 4 Dead 2, uses the same Source engine as the original title. Here the time demo that we recorded was a little less demanding, and as a result we saw the average frame rate for the Radeon HD 5970 jump by 20fps at 2560x1600. The card remained 52% faster than the Radeon HD 5870.