We saw the first wave of Radeon cards in the HD 4800 series hit store shelves last week, with the initial benchmarks showing the 4850 as a quite promising product for its suggested retail price of just $199. But there’s more coming from ATI and so now we shift our focus to the higher-end 4870, which has officially arrived today priced at $299.

Based on the same RV770 chip that powers the 4850, the new card is clocked higher at 750MHz and is the first to use newer GDDR5 memory technology that nets about 3.6 gigabits per second of headroom for its 800 stream processing cores. Besides clock speeds and memory type, the Radeon HD 4870 and HD 4850 are basically the same thing as both have the same number of transistors (956 million), use a 55nm manufacturing process, offer DX10.1 and Shader Model 4.1 support, and use ATI’s CrossFireX multi-GPU technology.

Benchmarks are already floating around the web, showing the Radeon HD 4870 is definitely a step up from Nvidia’s GeForce 9800 GTX+ and actually competes closely with the more expensive GeForce GTX 260, a $399 card based on a chip twice the size. Check out some reviews at Tech Report, HotHardware, AnandTech, and TweakTown.