Specifications & Features
Specifications & Features
Much like the Black series SN500 the SN550 is using (Triple-level cell written) written NAND flash memory from Sandisk. Western Digital's in-house NVMe SSD controller architecture derives from SanDisk and was cut-down into a more affordable two PCIe lanes no DRAM interface design. This allows them to offer the big storage volume at a lower price point. In 3D NAND, NAND cells in layers, not chips, are stacked in a single IC. The good news is continued cost reduction, smaller die sizes and more capacity per NAND chip. Also, installed NAND toolsets in the wafer fabs can, for the most part, be reused, thereby extending the useful life of the fab equipment. Though the numbers vary per model due to available NAND channels to the controller (big SSDs have more chips and channels to work with) these SSDs will be plenty fast for any regular performance metrics, offering double and even triple times the speed (depending on how you look at it) of the fastest SATA3 class SSD. As mentioned, Western Digital offers the product series in SKUs of 250GB, 500GB and 1TB
Specifications
 | |||
|---|---|---|---|
| WD Blue SN550 250GB | WD Blue SN550 500GB | WD Blue SN550 1TB | |
| Pricing | $48.99 | $64.99 | $109.99 |
| Capacity (User / Raw) | 250GB / 256GB | 500GB / 512GB | 1000GB / 1024GB |
| Form Factor | M.2 2280 | M.2 2280 | M.2 2280 |
| Interface / Protocol | PCIe 3.0 x4 / NVMe 1.4 | PCIe 3.0 x4 / NVMe 1.4 | PCIe 3.0 x4 / NVMe 1.4 |
| Controller | WD Architecture | WD Architecture | WD Architecture |
| DRAM | DRAMless | DRAMless | DRAMless |
| Memory | SanDisk 96L TLC | SanDisk 96L TLC | SanDisk 96L TLC |
| Sequential Read | 2,400 MBps | 2,400 MBps | 2,400 MBps |
| Sequential Write | 950 MBps | 1,750 MBps | 1,750 MBps |
| Random Read | 170,000 IOPS | 300,000 IOPS | 410,000 IOPS |
| Random Write | 135,000 IOPS | 240,000 IOPS | 405,000 IOPS |
| Endurance (TBW) | 150 TB | 300 TB | 600 TB |
| MPN | WDS250G2B0C | WDS500G2B0C | WDS100T2B0C |
| Warranty | 5-Years | 5-Years | 5-Years |
The WD Blue SN550 is an NVMe 1.4-compliant controller product with the host over a PCIe 3.0 x4 link, which is a big advantage over the SN500 which had an x2 link only. on the controller side not a lot is known, however likely the same one as the SN750 is being used, just cut down from eight to four NAND channels in use.
