The services, should be running and listed as automatic. Most Dells run on a sigmatel chip. But there are some compatibility problems in Windows 8. What do you have listed in the Device manager?
With Windows 8, on two dells I own, I have disabled and removed the Sigmatel drivers, and left Windows 8 to automatically install the
"High Definition Audio Device"
But try this download. It is for Windows 7, so use the compatibility option before installing. Best way is to uninstall any drivers under sound in the Device manager, do not reboot, and install the download.
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