Introduction

Crucial, a subsidiary of Micron, a world leader in memory and flash production, brought us such wonderful SSDs as the BX100 and MX100, which also came at an aggressive price point.

Today, we are reviewing the Crucial MX300 SSD, which introduces Micron's TLC 3D-NAND to the MX series. The MX100 and MX200 have used Micron MLC flash chips; the TLC flash on the MX300 is more cost effective because it can store three bits of data per cell, unlike the two bits MLC provides. This happens at reduced performance though, so the challenge for Micron is to enable MX-class performance with these TLC chips.


Pictured above, 3D NAND stacks several layers of storage cells vertically, which allows more storage in a smaller space, leading to fewer required chip packages, which results in cost and space savings.

Instead of a Marvell 88SS9189 controller, Crucial is now using Marvell's 88SS1074, which adds support for TLC flash and improves power consumption, among other things.

In order to boost TLC chip performance, to make up for the ground lost over MLC, 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. In terms of technology, the SLC cache is identical to the MX200 (not BX200).

Initially, the MX300 was only available in 750 GB capacity, but 275 GB, 525 GB, 750 GB (this review), 1 TB, and 2 TB versions have since been added. M.2 versions are available, too.

Packaging and Contents

The Drive

The drive conforms to the dimensions set forth by the 2.5" form factor. It is made of metal to improve its durability and is only 7 mm thick, which makes it compatible with Intel's Ultrabook specification.


Like most recent SSDs, the Crucial MX300 uses the SATA 6 Gbps interface. It is compatible with any older SATA standard, but will, in such a case, work at reduced performance.


You will find the SSD controller and eight flash chips on the PCB. A DRAM chip is also present; it provides the SSD controller with RAM.


The Marvel controller is a new variant that now supports TLC flash.


The eight TLC flash chips, produced by Micron, are built on a 15 nanometer 3D NAND process.