Introduction

Crucial's MX500 SSD Series was announced in December of last year and offers the first TLC-based SSDs that have convincing performance that's similar to what MLC drives provide. Our initial review was of the 1 TB variant, we reviewed the 500 GB version a few weeks ago, and today, we take a look at the M.2 version of the 1 TB MX500. Back when the MX500 was announced, only the 2.5" SATA versions made it to market and M.2 models became available just recently.

Just like the SATA models, the Crucial MX500 M.2 uses an SMI controller instead of the Marvell chips we saw on earlier MX-Series drives. It also uses Micron's own 64-layer 3D TLC NAND chips, which is a first for the company. While TLC chips provide cheaper cost per gigabyte over more traditional MLC NAND, they also come with lower write performance. In order to work around that, Crucial designates a small, variably sized amount of memory as SLC cache, which writes a single bit to each TLC cell instead of three. While much faster, such a setup is basically a speed vs. size tradeoff. According to Crucial, the SLC cache is variably sized to provide the best performance.

Unlike many other high-end SSDs on the market, the MX500 M.2 does not use the NVMe interface; rather, it uses the same SATA protocol as the 2.5" models do, which means performance should be pretty much identical to these, with M.2 adding the convenience of its form factor.

Packaging and Contents

Inside the package, you will find the SSD, some documentation, and an Acronis True Image download coupon.

The Drive

The drive uses the M.2 2280 form factor, which means it is 22 mm wide and 80 mm long. A thin copper foil, which has some Crucial artwork on it, acts as a basic heatspreader.


Note how the connector has two notches? These identify the drive as a SATA-based drive. So it is not using NVMe over PCIe like other high-end drives. This limits the transfer speeds to around 500 MB/s. You should be aware of the fact that you will "lose" one of the cabled SATA ports when connecting this drive. If your motherboard has six 2.5" SATA ports, for example, you will only have five of those active after installing an M.2 SATA SSD.


You will find the SSD controller and eight flash chips on the PCB. Two DRAM chips are also present to provide the SSD controller with RAM and soak up write bursts.


The SMI controller is a first for the MX Series, which used Marvell controllers before.


The eight TLC flash chips are produced by Micron and are built using 64-layer 3D TLC NAND technology.