Xbox 360 – will have southbridge from SiS

Xbox 360 will have a specially designed southbridge from the chipset manufacturer SiS. The role of the southbridge is to control and handle the flow of data between the different units, aside from the graphic circuit and the CPU which will be handled by the northbridge which will be designed by MS with support from ATi. What remains are USB-ports and harddrive(s). Especially the USB-ports will play a major part as MS has advertised for many accessories such as keyboard, camera, etc.

Source: xbox-scene.com