It probably is *NOT* a "jumper" setting on the motherboard.
Instead, restart the computer, and press DELETE to enter BIOS SETUP MODE.
Navigate through the menus, and you should find some "enable/disable" setting for the "OnBoard AC97 Sound". Disable, and "save settings", and let the computer reboot.
Answers & Comments
It probably is *NOT* a "jumper" setting on the motherboard.
Instead, restart the computer, and press DELETE to enter BIOS SETUP MODE.
Navigate through the menus, and you should find some "enable/disable" setting for the "OnBoard AC97 Sound". Disable, and "save settings", and let the computer reboot.