ATI Gives Chipsets a Try - Introducing the Radeon IGP

The X Stands for Communications

We mentioned earlier that ATI's Radeon IGP can interface either via a 32-bit PCI bus to a 3rd party South Bridge or ATI's A-Link bus to their own South Bridge. When using a 3rd party South Bridge you must keep in mind that none of the latest South Bridges (e.g. SiS 961, VIA VT8233A) can be used since they rely on proprietary links to connect to their northern counterparts. Instead, motherboard manufacturers will have to use an older South Bridge (e.g. VIA 686B) that uses the PCI bus to connect to the North Bridge. This makes opting for ATI's own South Bridge much more appetizing for motherboard manufacturers since these older 3rd party South Bridges obviously won't have the newest features.

ATI calls their South Bridges their Integrated Communications Processor, or IXP for short (there are actually two Xs in communications, can you find them?). What you won't find in ATI's IXP is a high-powered DSP capable of Dolby Digital Encoding, instead you'll find a fairly conventional South Bridge with integrated LAN and USB 2.0.

The primary features of ATI's IXP are its integrated 3Com 10/100 Ethernet controller and a 6 port USB 2.0 controller. ATI's IXP does not support Ultra ATA 133 mainly because of a lack of OEM support for the standard.

There are two versions of ATI's IXP at this point, the IXP 200 and the IXP 250. Both have the same basic feature set and use the same integrated 3Com Ethernet controllers and USB 2.0 controllers. The difference between the two comes in their targeted markets; the IXP 200 is aimed at the home user while the IXP 250 is aimed at the business user. The IXP 250 thus features support for remote wake on LAN, desktop management interface, ASF, etc… These are all features that aren't really necessary for the home user and thus the IXP 200 will suit most users just fine.

Again without any expensive DSP licenses, ATI's IXP should be priced competitively with ALi, SiS and VIA South Bridges. Although the first Radeon IGP chipsets will appear before then, the first IXP chips will be available in July of this year. Until then, motherboard manufacturers will have to rely on 3rd party South Bridges.