According to this story posted at Digitimes today, SiS has already begun volume production of the PCI Express-compliant south bridge chipsets, the SiS 965 and the SiS 965L, that will compete with Intel's forthcoming 915 (Grantsdale) chipsets. VIA and ALi are expected to follow soon.
On a related story, Dell has placed orders for PCI Express graphics cards with MSI Computer.