Radeon HD 5870 is without doubt, the most exiting thing that happened to consumer graphics in H2 2009, so far. While as a single graphics card, it lived up to its target of coarsely matching the performance level of a dual-GPU accelerator from the previous generation, in a pair it offers the kind of performance increments we have come to expect from multi-GPU setups of powerful GPUs. Radeon HD 5870 CrossFire serves as a good prelude to what AMD has in store in the form of a dual-GPU accelerator slated for later this year.
Although the overall performance gain over a single accelerator is 26%, don't give the overall figures too much importance. The figure includes performance measurements at several low resolutions such as 1024 x 768, 1280 x 1024, and even 1680 x 1050 pixels. The HD 5870 CrossFire simply isn't meant for these resolutions, and you're better off saving some money and power, and opting for a single accelerator. Where HD 5870 CrossFire feels comfortable is HD 1080p and above. At 1920 x 1200, the setup feels at home, and at 2560 x 1600, these cards shred through everything you throw at them, where every single graphics card, including dual-GPU ones begin to fatigue and crawl along.
As with every case where you're relying on two physical graphics cards to work in tandem, each brings with it, individual power requirements and added heat and noise outputs. We will talk about these at greater lengths when that phase of our review is complete.