NVMe and the 8th Gen I5 Nuk

AHCI is a HCI. Are you sure that like this is a chance a little be NVMe it's like the older one some of them had M SATA which that port is all kinds of weird. M.2 does not always mean NVMe as Alan said you might have M.2 PCIe or M.2 USB. It just chimes exactly with what you said about the RAM some will work and some just won't. Just any old cheap 120 gigs that a drive works no problem. I've got an eighth gen i5 nuk and for some reason it's very picky about NVMe drives that it will boot from or even see in the operating system. Well