The BG4 is Toshiba’s fourth-generation ball grid array SSD, combining NAND and controller in a single package. The new BG4 is a big step forward from the previous BG3 using Toshiba’s latest NAND technology and a new controller.
The BG4 uses Toshiba’s latest 96-layer BiCS4 3D TLC NAND and comes in four capacities; 128GB, 256GB, 512GB and the flagship 1TB drive. There are two formats; M.2 surface-mount 1620 single package (coded KBG40ZPZ) and removable M.2 2230 module (coded KBG40ZNS). It’s the latter we are looking at here, with the 1TB KBG40ZNS1T02 flagship drive.
The previous generation drive, the BG3, used a controller with a PCIe 3 x2 interface, which has been replaced in the BG4 with one that supports PCIe 3 x4. Instead of a DRAM cache it uses NVMe Host Memory Buffer (HMB) technology, which uses a portion of host memory (less than 100MB) to support caching demands.
Official performance figures for the 1TB drive are up to 2,300MB/s and up to 1,800MB/s for Sequential read/writes respectively with 4K random performance rated as up to 390,000 IOPS for reads and up to 200,000 IOPS for random writes.
- Usable Capacities: 1TB.
- NAND Components: Toshiba 96-layer BiCS4 3D TLC.
- NAND Controller: Toshiba.
- Interface: PCIe Gen3 x4 NVMe 1.3.
- Form Factor: M.2 2230-S3.
- Dimensions: 2.38 x 22 x 30mm.
Firmware Version: AEJA0102.