His mobo doesn't support NVMe Protocol so the adapter wont offer any speed benefit over a standard SATA III SSD.
However, if there's any plan to upgrade the mobo (within the next two years or so) to one with NVMe and the M.2 slot then I would keep the 960 for now.
I posted this same question on another forum and got the following response:
'The motherboard doesn't have an M.2. slot so the SSD is useless unless using an adapter card but as been said there's a good chance it may not be bootable. You could only use the SSD for an extra storage drive in that situation. Yeah i forgot about the possible not being able to boot off it thing.'
So apparently I may not be able to boot off the adapter?