Total War: Shogun 2
The performance boost in CrossFireX mode is high here, too: +85-97% at 1920x1080 and +95-98% at 2560x1600. But, unlike Sid Meier's Civilization V and Tom Clancy's H.A.W.X. 2, Total War: Shogun 2 can put the two cards to good use, running smoothly even at high resolutions with 4x MSAA.
A couple of Radeon HD 7970s is going to come in handy in Crysis 2 if your monitor supports resolutions above 1920x1080. CrossFireX technology is 65 to 72% efficient at 1920x1080 and 92 to 94% efficient at 2560x1600. Unfortunately, the bottom frame rate does not grow up proportionally to the average speed.
The CrossFire configuration is highly efficient in DiRT 3. It doubles both the bottom and average frame rate compared to the single card.
Hard Reset Demo
The CrossFireX configuration is unstable here. Its advantage over the single card varies from 16 to 95%.
Batman: Arkham City
The Radeon HD 7970 CrossFireX configuration is erratic in Batman: Arkham City, its performance fluctuating from -14% to +42% relative to the single card. We couldn't solve this problem by choosing different CrossFireX modes and the appropriate profile in the Catalyst control panel.
The CrossFireX configuration behaves erratically in Battlefield 3, too. Besides occasional hang-ups when loading the game, the pair of Radeon HD 7970s do not offer much in terms of performance. They are not any faster than the single such card at 2560x1600, for example.