AMD's upcoming Radeon HD4890 graphics card has already appeared in some online stores, available for pre-orders for about €260

Based on the AMD RV790 GPU, the Radeon HD 4890 will be using 800 stream processors and 40 texture units, while its 256-bit memory bus will be compatible with GDDR3, GDDR4 and GDDR5 memory. Sapphire's implementation of the Radeon HD 4890, which is currently listed online here, is equipped with 1024MB of GDDR5 memory and its GPU is clocked at 800MHz. The card has also 2 DVI ports and HDTV TV-out.

AMD Radeon HD 4890 is also listed at the PCI special interest group's web pages as it has been certified for compatibility. The first implementations of the new RV790 chip will appear in the beginning of April.