It's onboard sound, works through the cpu as opposed to a separate sound card. Their website's not helpful, but to get a handle on what you need, try start/RIGHT CLICK computer/manage & select device manager from the dialogue box & then look for sound & audio devices from the list - if the pc recognises it, it will be listed in detail there.
That should guide you in your search for a driver. Alternatively you can use the update driver option from device manager & tell shyster - sorry-Vista to search automatically for a new driver I.e. online. In my experience that works quite well & certainly worth a try.