To PXE boot a Microsoft Surface Pro 3 follow these steps:
- Plug in the Microsoft Ethernet Adaptor into the USB port
- I have tried other adaptors that other people say work, but I have not found success
- Power off the Surface – a reboot is not sufficient
- Press and HOLD the Volume DOWN button (on the left side of the tablet)
- Press and HOLD the Power button for FIVE seconds (on the top of the tablet)
- Release the Power button after five seconds but KEEP HOLDING THE VOLUME button until your see PXE start
- Have a nice day.