Performance in First-Person 3D Shooters
Aliens vs. Predator
Well, we already saw this all in our tests of the ASUS HD 6870 DirectCU. Clearly, Barts-based graphics cards need a GPU clock rate of 1 GHz or higher to match the GeForce GTX 560 Ti. Factory overclocking to GPU frequencies of 900-940 MHz is usually not enough for that. It's also clear that you need to overclock such cards in order to make this game playable at 2560x1600.
Battlefield: Bad Company 2
The MSI R6870 Hawk is expectedly in the lead when overclocked, but when the graphics cards from MSI and PowerColor work in their default mode, they deliver the same performance as they have almost the same GPU and memory clock rates. Overclocking is not rewarding at 2560x1600, by the way, as it ensures but a small performance increase which can hardly be worth the risk of putting the graphics card under stress conditions.
Call of Duty: Black Ops
This game having modest system requirements, the Radeon HD 6870 does not really call for additional or even factory overclocking. Every graphics card copes with the game successfully at 2560x1600. The standings are determined by the frequencies achieved in overclocking.
There is no point in overclocking a Radeon HD 6870 for Crysis because you cannot achieve a playable speed in the popular Full HD mode unless you resort to extreme methods like volt modding or cryogen cooling which can hardly be used as long-term measures.
This game is tested with the tessellation option turned on.
Our overclocked MSI R6870 Hawk takes first place, beating the GeForce GTX 560 Ti. Interestingly, the PowerColor is a little bit faster than the Hawk in the default mode, which is due to its more aggressive factory overclocking.
S.T.A.L.K.E.R.: Call of Pripyat
This game runs with enabled tessellation.
At 2560x1600 the performance of a Radeon HD 6870 is not affected much by overclocking in this game whereas at the lower resolutions the frame rate is high without our increasing the clock rates. The MSI R6870 Hawk and the PowerColor HD6870 PCS+ churn out no less than 28-30 fps, achieving an average 40-42 fps, which is quite enough for comfortable play.