Half-Life 2: Episode Two
The Radeon HD 4870 X2 wins this test. Although its lead over the GeForce GTX 280 is rather small at low resolutions, the gap grows to 8% and 30% at the more important resolutions of 1920x1200 and 2560x1600 pixels, respectively. The overclocking leads to a 4% increase in speed, which has no practical value. So, you may only want to overclock your HIS HD 4870 X2 just as a hobby unless you use some extreme overclocking methods. But if you overclock the card in an extreme way, it will hardly work for long in such a mode.
S.T.A.L.K.E.R.: Shadow of Chernobyl
The game doesn’t support FSAA when you enable the dynamic lighting model, but loses much of its visual appeal with the static model. This is the reason why we benchmarked the cards in S.T.A.L.K.E.R. using anisotropic filtering only.
There is an effect from overclocking at every resolution. For example, there is a 9-10% increase in the card’s bottom speed at a resolution of 1280x1024. The 50MHz growth of the GPU frequencies leads to a 6% growth of the average speed at 2560x1600. Like in the previous tests, this has no effect on your playing comfort.