Hello torrentg, thanks for your concern,
I had that problem with the chipset drivers
and I thought the same you did. Everest reported that the AGP was completely disabled. There is no update even in www.sis.com
and, additionally, the old XP drivers couldn't load, not by a long shot (system wouldn't even boot). By chance I found out that Windows Update offered SiS AGP drivers as an Optional (!?!?) Update. I downloaded and installed them and they actually... worked!!! Everest reported the AGP enabled and everything seems fine apart from the problem I described in this thread.