SiS have released both new AGP drivers as well as USB 2.0 for Windows 2000 & XP.
The AGP driver can be used for the following chipsets:
SiS648, SiS645DX, SiS645, SiS651, SiS650, SiS745, SiS740, SiS735, SiS733, SiS635, SiS633, SiS730, SiS630
Download:
SiS AGP Driver 1.11
SiS USB 2.0 Driver 1.0
Source: TecStation.de
The AGP driver can be used for the following chipsets:
SiS648, SiS645DX, SiS645, SiS651, SiS650, SiS745, SiS740, SiS735, SiS733, SiS635, SiS633, SiS730, SiS630
Download:
SiS AGP Driver 1.11
SiS USB 2.0 Driver 1.0
Source: TecStation.de