According to the manual, "The Ear Force PX4 is a premium, Dolby surround sound headset designed for PS3, PS4 and Xbox360 gaming.". I see nothing in the manual on how to make this work on a PC. Page 22 discusses using a 3.5mm cable to connect to a music player. Maybe that would work in the Alienware headset port? Not sure. We never tested this device.

I tried to do that. Some people managed to make it work, but they had the usual optical cable port on their computer. I don't know if the problem is that I don't have the S/PDIF port (I just have the Mini S/PDIF) or if my problem is that Alienware isn't compatible with Dolby Technology. If it is the first case, there is any other adaptor to make it work?

Thank you!

No idea. The 17-R3 ships with the onboard Realtek ALC3234 audio controller and Creative Sound Core 3D with SBX Pro Studio software. I do not see any reference to Dolby in the notes. Did you open the software and look for Dolby?

I opened the Sound Blaster Control Panel. There is no Dolby option there. Some people have this, but not me.