Crysis remains the de-facto gauntlet for GPUs. The HD 5870 doesn’t have what it takes to run the game at 2,560 x 1,600 with the best playable resolution proving to be 1,920 x 1,200. Even then we had to turn off the AA to see a smooth minimum frame rate of 28fps as 4x AA was too much for the card. Crysis has a loving relationship with the GTX 295 though and at 1,920 x 1,200 the Nvidia card was a considerable 10fps faster than the HD 5870, however in terms of a single GPU product the HD 5870 is still clearly faster than the GeForce GTX 285 and Radeon HD 4890 on average, but just marginally so in minimums.
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If you have a Radeon HD 4870 512MB or even Radeon HD 4890 then an HD 5870 would be a more worthy successor for the role of frame rate churning in your gaming rig but only really if you have a 1,920 x 1,200 monitor. For now, 1,680 x 1,050 users should be fine to wait out upcoming products and future game demands.
Quite honestly, after 18 months between the last and this generation it's not really a large enough jump in performance to make us very impressed by the performance for a £300 product. It's looking like ATI have made a GPU to fill the big shoes left by its RV770-based cards, which is no mean feat, and given the quantum leap in performance the HD 4000 series was over the HD 3000, it hasn't achieved it again in raw FPS this time around. That's not to say it's at all slow though: it's still the fastest single GPU product and if you want the fastest, most future proof product available we'd recommend it, however it's not an "I must upgrade now" product. We'd wait that one out.
