The Western Digital WD Black SN850X 2TB wins in 3 out of 7 comparable specs. Its biggest advantage is DRAM Cache (100% better).
WD Black SN770 2TB wins in 1 spec (MSRP: 29% better).
Recommendation
Choose WD Black SN850X 2TB if you want the best overall performance — especially dram cache.
Choose WD Black SN770 2TB if msrp matters more to you.
| Spec | Western DigitalWD Black SN770 2TB | Western DigitalWD Black SN850X 2TB |
|---|---|---|
| Storage | ||
| Capacity | 2000 GB | 2000 GB |
| Type | NVMe SSD | NVMe SSD |
| Interface | PCIe Gen4 x4 | PCIe Gen4 x4 |
| Form Factor | M.2-2280 | M.2-2280 |
| NAND Type | TLC | TLC |
| Performance | ||
| Sequential Read | 5,150 MB/s | 7,300 MB/s+42% |
| Sequential Write | 4,850 MB/s | |
| 6,600 MB/s+36% |
| Endurance (TBW) | 1,200 | 1,200 |
| Features | ||
| DRAM Cache | No | Yes+100% |
| Platform | ||
| Controller | WD in-house | WD in-house |
| PCIe Gen | 4 | 4 |
| Price | ||
| MSRP | $100−29% | $140 |
| Release Date | Feb 2022 | Aug 2022 |