How to Install Windows 8.1 in UEFI Mode
Windows 8 / 8.1 support for advanced boot method called the UEFI (Unified Extensible Firmware Interface) which is developed for providing Security and Stability to the Computer System.
Download Windows 8.1 UEFI ISO
For more details regarding UEFI visit Microsoft's Official Website:
Rufus USB Tool :http://sh.st/cnDSG or https://rufus.akeo.ie/