NO AUDIO DEVICE OUPUT IS INSTALLED

[bdock912]

Had the same problem with an eMachine and a Realtek sound card but this will work with any card you have. The issue is Vista's requirement for drivers to be Signed in a specific manner. Here's how to get around it:

Download the latest driver for your sound card to your PC
Uninstall the existing driver from the control panel/Programs section if it's there and/or from the Device Driver screen
Restart the PC and hit F8 to get the boot menu before vista starts loading
Select the option to boot without Driver Signing requirement
when the PC starts it will install a generic driver and the sound should be back
install the driver you downloaded in step 1 above
Restart once again and you should be as good as new