strictly speaking, the chipset on a64 boards handles the interface between the peripherals, since the memory controller in all K8 CPU's connects directly to the memory. (K8 CPU's include all socket 754, 939, and 940 CPU's, including Semprons, Athlon64, and FX)
Chipset is responsible for IDE control, onboard sound, onboard video, onboard ethernet, among other things. Probably the most important job for K8 chipsets in the interface for graphics, like AGP or PCIe.
SiS isn't really a top tier model, but it should get the job done.
Ep, glad to see you come back and tidy up...did want to ask a one day favor, I want to enhance my resume , was hoping you could make me administrator for a day, if so, take me right off since I won't be here to do anything, and don't know the slightest about the board, but it would be nice putting "served administrator osnn", if can do, THANKS