I am using windows vista x64 Enterprise on my ASUS K8V(AD1980 on-board sound card) motherboard. When I installed the OS, it automatically installed AC97VIA sound driver. The problem is that the S/PDIF doesn't work at all(selecting the enable S/PDIF menu doesn't work). I have tried to install Vista 64 bit driver, but all the install files(more than 30times) that i tried doesn't seem to contain smwdm.sys, so the installation failed.. Installing XP 64x driver didn't also seem to work out as well.. When I tried to install them manually(after setting bcdedit -set nointegritychecks yes)I kept saying that it's not compatible driver.. Any ideas..? It is very frustrating..