There are also some network software solutions to create a virtual screen capture on a host PC and a display on a remote target PC such as MaxiVista and ZoneOS ZoneScreen but these won't work with XBOX. The intent behind those tools is to take some throwaway laptop and use it as a second screen for your new laptop. I'm not sure how well these tools work in Windows 8.1 but you can give it a shot. There might be a way to do this with Microsoft RemoteFX too.
Miracast Receive – exposes a set of Wi-Fi direct APIs for Independent Hardware Vendor (IHV) drivers or OEM drivers to develop Windows 32-bit applications that run on all supported x86-based or x64-based versions of Windows 8.1, enabling the computer as a Miracast receiver.