The ATI Radeon 5870 1GB and HD 5850 1GB cards are marked purple in the diagrams. The new Radeon HD 5770 1GB and 5750 1GB and their CrossFireX configurations are marked red. The GeForce GTX 260 896MB is traditionally green while the old Radeon HD 4770 512MB is blue. Let’s start with synthetic benchmarks.
The CrossFireX configurations are both faster than the top-end single-chip cards in 3DMark 2006. The two junior Radeon HD 5750 are not only ahead of the single Radeon HD 5850 but stop very short of the Radeon HD 5870! This is an impressive result considering the difference in price. As for the single cards, the Radeon HD 5770 is competing with the GeForce GTX 260 and is expectedly superior to the Radeon HD 4770.
We see a different picture in the newer and more demanding 3DMark Vantage. The CrossFireX tandems, although delivering impressive scalability over the single cards, are no match to the Radeon HD 5870 and HD 5850. The GeForce GTX 260 is a little better than the Radeon HD 5770. The latter routs the Radeon HD 4770.
Unigine Heaven Demo
According to the heavenly demo from Unigine, the CrossFireX configurations are faster than their single-GPU opponents Radeon HD 5870 and HD 5850. The two junior Radeon HD 5750 cards are as fast together as the single Radeon HD 5870. The high results of the GeForce GTX 260 and Radeon HD 4770 (in ordinary mode) are due to the lack of DirectX 11 support whereas the cards based on AMD’s new GPUs all work in DirectX 11 mode.