What do solid-state drives SATA and M.2 mean, which one is better?


SSD interface

At present, there are four common SSD interfaces, namely SATA, M.2, mSATA and PCI-E.

SATA and M.2 solid-state hard drives are frequently contacted by ordinary consumers and are currently in the mainstream.

The mSATA solid state drive has been popular in the past few years, and now it has been basically replaced by M.2.

PCI-E solid-state drives have high prices and high-end positioning. They are generally found in the chassis of local players or commercial-grade servers.

So let's focus on SATA and M.2 solid state drives.

SATA, M.2, mSATA three interfaces

PCI-E interface

SATA solid-state hard drives are relatively simple, basically only a 2.5-inch version, and the appearance is no different from traditional 2.5-inch mechanical hard drives. The channel used is SATA, and the continuous reading peak is about 550MB/s.

The M.2 solid-state drive is more complicated. There are three versions, namely B key interface, M key interface and B&M key interface. The difference between the three lies in the position of the fracture at the golden finger and the number of pins on the short golden finger.

The notch of the B key interface is on the left, and the number of pins on the short side is 6. At present, there are not many M.2 SSDs with B key interface on the market, and the channels used are SATA or PCI-E×2.

If it is a SATA channel, the peak value of continuous reading is about 550MB/s. If it is a PCI-E×2 channel, then the peak value of continuous reading can exceed 700MB/s.

B key interface

The notch of the M key interface is on the right, and the number of pins on the short side is 5. Most of the M.2 solid-state hard drives with M key interface on the market are high-end products, and the channel used is PCI-E×4.

The SSD with this interface is very fast, the continuous reading speed can easily exceed 1600MB/s, and the flagship product can reach 3300MB/s.