S.T.A.L.K.E.R.: Call of Pripyat
We’ve got very interesting results in this game. The two pairs of AMD Radeon cards are only 56-68% faster relative to the respective single cards. The GeForce GTX 460 SLI is far more efficient at 96-97%. The reason for such an unassuming performance of the new Radeons is in the driver because AMD’s graphics cards have always been as good as their Nvidia opponents in this game, also in multi-GPU configurations. Running a little ahead, we can say that this is not the only game in which the new Radeon cards are let down by their driver.
CrossFireX didn’t work smoothly in Borderlands before, so we can't expect anything exceptional from it now. Its efficiency varies from 40 to 50%. SLI technology is 93% efficient, helping the GeForce GTX 460 tandem win this test. The overclocked Radeon HD 6850 is a mere 3-5% behind the reference Radeon HD 6870.
Grand Theft Auto IV: Episodes from Liberty City
Grand Theft Auto IV: Episodes from Liberty City is a third game in this test session where CrossFireX technology is less than 95-100% efficient. However, AMD's solutions are superior to Nvidia's in this game, our overclocking not helping the GeForce GTX 460 change this situation.
Left 4 Dead 2: The Sacrifice
Oddly enough, CrossFireX proves to be incompatible with the latest game in the Left 4 Dead series. The CrossFireX tandems both fail in this test. On the other hand, the single Radeon HD 6850, let alone the HD 6870, is ahead of the more expensive GeForce GTX 460. By the way, the Radeon HD 6870 is 7-10% faster than the Radeon HD 6850 working at the same frequencies.