The performance is achieved by simple arithmetic: combining two ATI Radeon HD 4800 series GPUs into a single card, and a whopping 2GB of onboard memory -- the most of any graphics card on the market. The HD 4870 x2 is the first card that supports AMD's upcoming "Cinema 2.0" effort. However, until there's software that supports the endeavor, purchasers of AMD's latest cards will have to simply appreciate playing current games like Oblivion at 2560x1600 with 24X AA -- y'know, the way games are supposed to be played.
The ATI Radeon HD 4870 X2 is immediately available from various "e-tailers" with a pricetag of $549 SRP. A cheaper, less powerful little brother, the ATI Radeon HD 4850 X2, will be available in September at an estimated price of $399.