I think its an onboard card, part of the motherboard. I used the Belarc Advisor Profile of my computer and this is the motherboard spec:
Board: SiS-651
Bus Clock: 100 megahertz
BIOS: Phoenix Technologies, LTD 6.00 PG 04/08/2003
I did a google search for the audio drivers for that, and got SiS 7018 audio driver. I use the installation wizard and it goes halfway then the wizard closes with no error message. In device manager the 7018 has a yellow exclamation mark next to it, and when i try to update or re-install, I get the error message "the hardware was not installed becuase the wizard cannot find the necessary software".
I've now tried downloading the ZIP file for the 7018 drivers. I used the "WINXP" folder, and selected the driver in there. The PC copied the files over, but then I got the error message "The device cannot start (Code 10)" Any idea why?