Micron P400m Internals

The Micron P400m comes in a 2.5-inch form factor with a 7mm Z-height. This enables deployment into slim applications and blade servers.

Once opened, we can observe that Micron is using thick thermal pads to shed heat form the controller and NAND into the case of the SSD. This creates a heatsink effect, helping to lower the overall heat of the SSD. This increases the longevity of the components.

The P400m has a generous helping of overprovisioning, weighing in at 70%. This provides ample space for internal functions and the RAIN implementation.

There are 16 emplacements of custom 25nm MLC NAND on the PCB, with 8 per side. Each of the three capacity points (100, 200, 400GB) will utilize the same number of NAND packages with a varying die count per package. The 100GB capacity will feature Dual die, the 200GB capacity has Quad die, and the 400GB will feature 8 die per package.

This NAND is an SSD-specific design and will not be available to Micron's customers on the open market. The MLC NAND manages to increase endurance without sacrificing performance, and features an 8KiB user page size with 256 pages per block.

There are also four yellow capacitors along the edge of the PCB. These capacitors will flush data to the NAND in the event of a host power-loss issue. We do note that there are several open slots for more capacitors, possibly for higher capacity versions of the P400m.

There are other open mounting points for capacitors on the bottom of the PCB and the remaining 8 NAND packages.

The Marvell 9187 SSD controller dominates the front of the PCB near the SATA controller. This controller has a long track record of reliability in the enterprise space. The Marvell controller is powered by Micron custom-built firmware. This firmware is designed and optimized to interact with their onboard NAND and DRAM. The controller is flanked by a 50nm 2GB DDR2-800 DRAM module.