The ATI Radeon HD 4850 is a video card reference specification designed by AMD/ATI. It includes a 55nm RV770 GPU (graphics processor) and 512MB or 1GB of GDDR3 memory connected through a 256-bit interface. With 956 million transistors, it almost doubles the performance of ATI's last higher end card single GPU card, the Radeon 3870 - toping its own last generation model the 3850 by an even larger margin. Launched at a suggested retail price of 199 dollars, the Radeon HD 4850 has been selling quite well, beating or at the very least matching Nvidia's offerings in performance as well as price.