Full Details from Amazon.com : http://www.amazon.com/gp/product/B001L1RZ00?tag=onigi-20
Sapphire Radeon HD4870 512MB DDR5 Dual DVI / TVO PCI-Express Graphics Card
PCI-Express x16 bus interface
256-bit DDR5 memory interface
Microsoft DirectX 101 support
OpenGL 20 support
Unified Superscalar Shader Architecture