M.2 Slots – SATA and NVME SSDs

A quick hardware episode today because every now and then I was puzzled about how to identify if an M.2 SSD is a SATA drive or if it supports the faster and today’s more common NVME interface. The same goes for the M.2 connector on the notebook side. Turns out it is quite simple.

In practice, the M.2 SATA SSDs I’ve come across always have two notches in their connector. They are ‘B and M keyed’ as per the M.2 standard. In theory, B and M keyed M.2 SSDs can also be older NVME drives limited to 2 PCI-Express lanes, but I have never come across such devices so far.

NVME M.2 SSDs on the other hand only have one notch in the ‘M’ position. These are definitely not SATA drives. So in summary I associate 2 notches with SATA SSDs and 1 notch with NVME SSDs.

In notebooks, I’ve only come across connectors so far that are ‘M’ keyed. In other words, they accept both SATA and NVME SSDs. The big question is then whether both SATA and NVME is supported. So far, I’ve come across two older notebooks with one M notch, and both had a B&M notch SATA M.2 SSD inside. Both maintenance manuals state, however, that they support SATA and NVME SSDs. The picture above shows the SSD and the mainboard of one of those notebooks, so this should make things even clearer.