Is it an onboard-video controller? If it is, search the website of the mainboard's manufacturer for drivers. There you should also find drivers for an onboard audio-controller.
If it is an AGP/PCI video card, check the card itself for all sort of labels/numbers/keys written on it, and then use Google.
an email would be better for me cos i get lost around these sites!!
You get your Email, because you are subscribed to this thread. If you get lost, use bookmarks.
Michael