real world even using a old sata based SSD for JUST the OS would be fine......I have a old 256gb samsung in the gaming rig and it still boots in 10 seconds.....but i have a 2tb gen 4 M.2 and a 1tb gen 3 M.2 as well as 2 512gb sata SSDs for all my games.....in the pic below are the speeds of all...