The following was suggested to me:
Go to the BIOS, press F2 at the Dell logo, Press Caps Lock, Num Lock and Scroll Lock, so that all the three lights are lit up. Then press Alt + E. Your system will beep. Restart the computer. Check the sound options in the control panel. If this still does not work, reinstall the sound drivers, by first uninstalling them in safe mode.
Is this a wise thing to do? I don't want to blow up my PC.