Driverheaven posted a review on the ATI Radeon HD 5870 Graphics Card
A quote from the article:
>> ATI Radeon HD 5870 Graphics Card Review
In order to take full advantage of Microsoft's latest DirectX we require hardware which supports features such as Shader Model 5 and today we bring you the launch of the world's first publically available DX 11 hardware, the Radeon 5870.
>> ATI Radeon HD 5870 Graphics Card Review