Just six short months after releasing the Radeon HD 2400 and 2600 series graphics processors, AMD has announced replacements for those chips. Two of the new cards make up the Radeon HD 3400-series, the HD 3450 and HD 3470, while the remaining card is called the Radeon HD 3650. Like the 3800 series, AMD's new low-end GPUs have also made the transition to a smaller, 'half-node' 55nm fab process. Tops among the changes is support for DirectX 10.1 and Shader Model 4.1, a minor revision to the DirectX spec that offers game developers better control over antialiasing hardware and exposes a new capability, cube map arrays, intended to improve performance with global illumination algorithms. Many of the other changes simply amount to better plumbing-often necessary but rarely sexy. Among them: support for PCI Express version 2.0, which effectively doubles the bandwidth available between the GPU and the rest of the system

The two chips, code-named RV620 and RV635, will replace the current RV610 and RV630 GPUs. The more potent of the two, the RV635, powers the Radeon HD 3650 graphics card. The Radeon HD 3650 will come in two flavors. The tastier of the two will have GDDR3 memory onboard clocked at 800MHz, and the blander model will use DDR2 memory at 500MHz. Memory sizes will range between the standard-issue 256MB all that way to the goofy 1GB, for those who like lots of RAM on their $79 video cards - you know, as ornamentation. Both flavors will pack a 725MHz core clock, which is up somewhat from the 2600 Pro's 600MHz core. As a result, the 3650 should offer slightly better performance than its predecessor. AMD rates HD 3650's power consumption at 75W, and as a result, it should be able to get all of its power through the PCIe slot without the need for an auxiliary power plug.