Diamond Viper ATI Radeon HD 2600 PRO OVERCLOCKED 512MB PCIE GDDR2  Video Card PCI Express x-16 Radeon HD 2600 PRO OC with 600 MHz clock and 512 MB of 128 Bit-GDDR2 Memory 1 GHz effective memory speed Dual DVI and HDTV Support Optimized for Windows Vista with Direct X 10 support