As many of you are no doubt aware, AMD is about to release a new line of ATI Radeon graphics cards based on the GPU that was internally codenamed RV770.  Cards based on the GPU were supposed to launch next week, on June 25 to be specific, but due to some unforeseen circumstances, we are able to offer you some preliminary information and benchmark scores a little early.Like the RV670 used on the Radeon HD 3800 series, the RV770 GPU powering the Radeon HD 4850 is manufactured on TSMC’s 55nm process node.