iXBT Labs posted a review on the ATI Radeon HD 5850/5870/5970 Graphics Cards
A quote from the article:
>> ATI Radeon HD 5850/5870/5970 Graphics Cards Review
Today we shall review a few more high-end graphics cards belonging to the Radeon HD 58xx/59xx series. These solutions have had a great start. Radeon HD 5870 still remains the fastest single-GPU graphics card, while Radeon HD 5970 remains the absolute champion in today's 3D gaming graphics.
>> ATI Radeon HD 5850/5870/5970 Graphics Cards Review