You may need a software package for your sound in addition to the driver. Look on the PC model's Support Downloads webpage under Software and Hotfixes for any sound issues.

If not uninstall the sound driver in Control Panel>Programs and Device Manager, run Driver Sweeper on it to get rid of any sound driver leftovers, then reboot and run Windows Updates to see what driver it wants for sound. If none, import it from the PC's Downloads webpage.