Try:-
http://www.astra32.com/download.htm
Also:-
http://www.cpuid.com/pcwizard.php
Astra32 and PcWizard supply system information, and might identify your onboard sound. Often it is helpful to download the xp drivers before you wipe your system.
A useful program for identifying drivers is DriverView from:-
http://www.nirsoft.net/utils/driverview.html
Often Helpful
June 2008