Packaging

The Drive

The drive uses the M.2 2280 form factor, which makes it 22 mm wide and 80 mm long.

On the PCB, you'll find the controller and just one flash chip; a DRAM cache chip is not installed, and the other side of the PCB is empty.


While most other M.2 NVMe SSDs transfer data over the PCI-Express 3.0 x4 interface, the WD Black SN770 connects to the host system using a PCI-Express 4.0 x4 interface, which doubles the theoretical bandwidth.

Chip Component Analysis

Almost nothing is known about the new SanDisk 20-82-10081-A1 SSD controller. It is a four-channel design, which obviously supports TLC and DRAM-less operation. Unlike the controller on the WD Blue SN570, it has support for the fast PCI-Express 4.0 interface.


The flash chip is 112-layer Kioxia/Toshiba BiCS, rebranded by SanDisk, who are now part of WD. WD operates a joint-venture with KIOXIA to produce these NAND chips.