An Overview of mSATA and M.2 SSDs

With the increase in motherboards and systems supporting mini-SATA (mSATA) and M.2 standards for SSDs, and increased demand from them being included in more than just portable devices, we have seen some recurring confusion. This has mostly been related to basic compatibility.

The most important thing to remember when dealing with these standards is it's best to refer to your system documentation, or a resource like the the Crucial® System Scanner tool, to check the compatibility of SSDs with your system. Some of these systems require PCIe-based devices, while others require SATA-based devices. Some can use both, but might need to be configured to one mode or the other in your system's UEFI or BIOS. The standards are not interoperable even though the pinouts and slots may be similar or identical. This is the single most frequent issue we see regarding problems with installation of these drives, and it might require returning a drive so one with the correct compatibility can be used instead.

The mSATA form factor is relatively straight-forward in terms of compatibility. The only issue we've seen has been with users trying to put them into a mini PCIe slot not capable of also supporting mSATA. While the slot is identical, and some motherboards do support both, a PCIe®-only slot/motherboard will not run any of Crucial's mSATA drives.

M.2 drives, also known as Next Generation Form Factor (NGFF), feature multiple form factors based on the drive dimensions, layout of NAND components, and keying of the pins of the drive's connector. Crucial drives currently ship in a 2280 form factor (22mm by 80mm, either single-sided or dual-sided NAND layout), with B and M keying notches to maximize compatibility for SATA, and M-keying only on our NVMe® PCIe drives. Some M.2 slots have different keyings, such as A and E-keying. Crucial's current drives will not fit in these keyed slots, which are usually reserved for wi-fi and bluetooth adapters. 

It can't be stressed enough to verify, using your hardware documentation or any other support resources, that your system will support a given drive before purchase. This will save you time trying to diagnose and fix detection problems often being caused by a simple difference in protocol between your socket and storage device, and ensure the easiest installation experience possible.