Try the Driver Download pages at the Support website for your machine's vendor first (some machines, notably Dell and HP/Compac, use proprietary drivers), and if nothing relevant turns up there, look
HERE[/i][/b].
Its a good idea to backup existing drivers - just in case - then uninstall them, before installing the freshly downloaded updated drivers, BTW.
Oh, yeah - and check the card's Properties in Device Manager to determine the exact model and version of your card and the version of its installed drivers before doing anything else.