tomshardware[.]com/pc-components/motherboards/are-your-motherboards-m-2-heatsinks-making-good-contact-with-your-ssd-we-tested-20-modern-intel-and-amd-motherboards-to-verify
One of my pet peeves concerning external housings and heatsinks for M2 / NVMe drives is that they usually include a piece of putty-like tape to bridge the gap between the chips on the drive and the metal housing or heatsink, and that tape is most often too thin. It's supposed to act like the heat sink compound applied between the heatsink and the CPU, transferring heat to the metal where it dissipates, but if it doesn't make contact with both surfaces, you don't get that heat dissipation.
This article proves my point by checking several motherboards that come with M2 drive heatsinks. Sadly all you can do is buy your own tape from some place like Amazon and trial & error the thickness needed -- you should be able to see a faint indentation of the NVMe's chip after pressing the heatsink in place or closing the housing.
