"The ATI Radeon HD 38XX series are the first graphics cards in the world to support DirectX 10.1 capabilities and plug-and-play ATI CrossFireX multi-GPU upgradeability. CrossFireX is similar to CrossFire, but up to four graphics cards are paired together this time around. If you would like to run eight displays or want the ultimate gaming performance from AMD – CrossFireX is the way to go, but you have to use an AMD 790FX motherboard with four x16 PCI Express lanes to make it possible. DirectX 10.1 brings awesome new lighting features like global illumination to reality, but in order to support Microsoft DirectX 10.1 these cards will need to be used on a system with Microsoft Vista SP1, which isn’t due out till sometime in 2008..."