The GT76 Titan is the MSI laptop built with a desktop CPU socket on the motherboard, so it can use LGA1151 CPUs.
The Alienware Area 51m is the dell laptop with the same desktop CPU socket also.
Good question - for MSI to answer. Only the laptop manufacturer knows what THEIR bios supports.
A processor must be SOCKET, CHIPSET, AND BIOS compatible. Socket alone is not enough.