Audio problems

 

Like alot of people i've been getting No audio out put device detected, but the problem is i am unsure what model of the C-Media AC 97 i have i've checked onboard it doesn't say, the manifactuers website says that i have a (Soundcard Driver C Media AC 97 (onboard) soundchip. ) but no model number. i checked the C-Media website but they have no vista drivers for the 64 bit edition of ultimate. Is there a audio driver that i can get online some where to fix my problem?