The Cpq Presario 70x uses 2 chipsets from Via (www.via.com.tw)
Northbridge VT8362 and Southbridge VT82C686B (I've opened my laptop to see it!).
The VT8362 is a bridge with integrated S3 ProSavage4 (codename TwisterK !).
On the Via site you can search for system drivers (4in1 (AGP,...)) for all OS (Linux too) and Audio driver (integrated in VT82C686B) and Video for Linux. For Windows OS they give a link with the site ranger.s3graphics.com (login and pass given on via site) where you can find the drivers for the TwisterK for all Windows OS !!!
I've tested it on a Win2000 advanced server after having installed the 4in1 ver 1437a and it works fine.
Good luck, for any more question see my email address.
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