updated 07:45 am EDT, Wed June 25, 2008
AMD ATI Radeon HD 4870
AMD this morning publicly rounded out its video card updates with the full launch of the ATI Radeon HD 4800 series. The launch supports earlier low-key announcements but marks the formal appearance of the higher-end Radeon HD 4870; the double-slot card is said to be twice as fast as an equivalent Radeon HD 3870 card and performs at about 1.2 teraflops per second, or enough floating-point math calculations to generate help generate AMD's purportedly near-realistic Cinema 2.0 experience with high detail, many objects, and camera-like focusing effects.
The 4870 is clocked the fastest of the new cards with a 750MHz core speed and is the first to use extra-quick GDDR5 memory that nets about 3.6 gigabits per second of headroom for its 800 stream (pixel and vertex) processing cores.
Unlike with some past video card generations, the Radeon HD 4850 is now known to be virtually feature-identical to the 4870 and simply reduces clock speeds; the same 800 cores are intact, but the overall speed throttles back to 625MHz while AMD chooses older GDDR3 memory that can handle 2 gigabits per second. The speed reduction is enough to let AMD fit the 4850 in the space of a single card slot.
Both chipsets have similar 3D features to the Radeon HD 3000 series and can generate more advanced DirectX 10.1 and OpenGL 2.0 visuals; new to the 4800 line is more explicit general-purpose GPU support and improved movie acceleration that includes faster transcoding, picture-in-picture HD, and pass-through for 7.1-channel surround sound on cards that use HDMI.
The two boards are shipping today both as reference cards through AMD's ATI label as well as through third-party producers such as ASUS, Diamond, and MSI. The Radeon HD 4870 aims to oust NVIDIA's GeForce GTX 260 by performing as well or better at a $299 price tag for a 512MB version, or $100 less; the Radeon HD 4850 competes with the GeForce 9800 GTX+ at an official $199 versus NVIDIA's $230.
Radeon HD 4870
Radeon HD 4850