M.2 SATA = SATA drive only
M.2 NVMe = NVMe drive only
M.2 NVMe + SATA = NVMe or SATA drive

Reason : The other end of wiring is simply different.
SATA drive needs to connect to SATA controller.
NVMe drive needs to connect to PCI-E host (processor/chipset/switch).

Why M.2 NVMe + SATA works on both? Part of the connector goes to PCI-E host and another part goes to SATA controller.

This post has been edited by kingkingyyk: Oct 3 2020, 08:23 PM

Nope, because the case doesn't provide PCI-E wires for NVMe to work. (For that, you need U.2 case instead)
Currently way of working :
Host (Processor/Chipset/Switch) --(PCI-E)--> NVMe SSD
SATA Controller (Processor/Chipset) --(SATA)--> SATA drives
Host (Processor/Chipset/Switch) --(PCI-E) --> SATA Controller (Dedicated) --(SATA)--> SATA drives

This post has been edited by kingkingyyk: Oct 3 2020, 08:29 PM

Nope, the wire simply doesn't exist. Use U.2 case instead.

https://shopee.com.my/U.2-SFF-8639-To-NGFF-...4585.2193230588
Notice the connector on the case, it is different.

The SSD will run burning hot and data lost might happen due to insufficient power from USB

This post has been edited by kingkingyyk: Oct 3 2020, 08:33 PM

There are 2 types.
USB -> PCI-E controller, then connect to NVMe SSD
USB -> SATA controller, then connect to SATA SSD

U.2 contains wiring for PCI-E, so the other end of U.2 will go to PCI-E, not SATA controller.

------------------------------------
You have to understand the one physical connector doesn't necessary work in 1 way. There can be different signals.

This post has been edited by kingkingyyk: Oct 3 2020, 08:38 PM