1. Try using a live Linux distro to see if you have sound.
2.If you have sound with Linux , it's still a software/driver issue.
3. Restore to factory condition and see what happens..
4. If you still have no sound contact Alienware for warranty repairs.
Quite simply after updating to Windows 10 I've have had no sound on my computer for months now and don't know what to do. I've updated drivers like 12 times and I still don't get any sound and it's annoying having to put headphones in all the time. I have an Alienware and the crappy part is that I'd only had it a couple weeks before it happened. It happend right after the update so I'm guessing it has to do with something on the OS. Please help. Thanks.