Both leading designers of graphics processors – ATI Technologies and NVIDIA Corporation – said they are in process of shipping graphics chips and cards with PCI Express x16 support to their customers. The announcement indicates that transition to the new bus is on the roll.

PCI Express is a next-generation internal interconnection for personal computers that will exist in certain speed incarnations, e.g., x1, x4, x16. The PCI Express x16 lane is intended primarily for graphics cards, works at about 2.5 gigatransfers per second and is able to pump up to 8GB of data in each direction. Due to totally different transfer protocol from the AGP 8x bus, the PCI Express also has some other advantages over AGP, such as isolated read and write channels, ability to prioritize the data streams and a number of others.

While both NVIDIA and ATI are ready to offer their latest graphics processors to clients who plan to acquire personal computers with PCI Express x16 bus (PEG x16), approaches the companies used to add PCI Express interface into their chips seem to be different. ATI Technologies uses built-in PCI Express x16 controller and is able to offer fully-featured so-called “native PCI Express” solutions. NVIDIA uses a special chip that bridges its AGP graphics processors with PCI Express x16 platforms. NVIDIA claims that PEG x16 bandwidth or bi-directional transfer ability are not sacrificed as a consequence of its “bridge approach”, though, certain PCI Express functionality may not be enabled on NVIDIA’s graphics cards with the HSI bridge, some analysts said.

ATI Technologies currently offers RADEON X300, RADEON X600 and RADEON X800 series of graphics processors with PCI Express x16 interface targeting entry-level, mainstream and high-end markets. NVIDIA targets the same market segments with its GeForce PCX 5300, GeForce PCX 5750, GeForce PCX 5900, GeForce 6800 GT as well as GeForce 6800 Ultra graphics cards supporting PCI Express x16 interconnection.

Computer makers and retailers worldwide will start shipping PCs and graphics cards with PCI Express x16 interface shortly.

Smaller graphics chip designers, such as S3 Graphics, 3Dlabs and XGI Technology, are likely to jump on the PCI Express x16 bandwagon a bit later this Summer.