Four diminutive screws are all that holds the backplate on the Crucial M550 drive. Fortunately for us, there was only one small void sticker over a screw and no other anti-intrusion features employed.
Four more screws hold the PCB and there’s a thermal pad between the controller and the shell of the drive which sticks them together making it a little harder to remove.
The first side of the PCB contains only the NAND modules with eight total on this side.
The 20nm Micron MLC NAND chips on the 512GB drive is 128Gb in density whereas the smaller drives use 64Gb chips. They carry part number 3ZA2D NW386.
The flip side of the board also contains eight NAND modules for a total of 16 on the drive, along with the controller and cache chips.
The cache ship carries FBGA code D9RLT which corresponds to part number MT42L256M16D1. This is an LPDDR2 SDRAM part that has a capacity of 4Gb (512MB). This works in tandem with the Marvell 88SS9189 which is the next generation controller from the 88SS9187 that we saw on the M500. It handles all of the usual duties like TRIM and garbage collection along with wear-leveling tasks. It also supports AES 256-bit hardware encryption and is responsible for overseeing the RAIN (Redundant Array of Independent NAND) technology we discussed in the article opening.