A couple of our customers recently reported to us that High Performance mode was missing from their devices following an upgrade to Windows 10.
Thankfully a small registry change can be performed on the device to enable this option:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Power
Change the value of CsEnabled from 1 to 0.
Following a reboot the High Performance mode will now appear in the Power Options in Control Panel!