if you get the error
No Bootable Device error when booting to Dell Windows 10 media
it is because all Dell Windows 10 recovery media (Win10 recovery DVD [Clean install only from DVD] or WIN10 recovery USB key) require the system BIOS to be configured in the Unified Extensible Firmware Interface (UEFI) mode.
There will be no changes made to the Dell Windows 10 recovery media because, as by Microsoft design, Windows 10 is intended to be used in the UEFI mode configuration.
but that CANT be true ? i am sure i have a Lenovo Thinkpad that only has BIOS (not UEFI) that works fine with Windows 10 !