The Western Digital WD Black SN850X 2TB wins in 5 out of 7 comparable specs. Its biggest advantage is Capacity (100% better).
UD90 1TB wins in 1 spec (MSRP: 68% better).
Recommendation
Choose WD Black SN850X 2TB if you want the best overall performance — especially capacity.
Choose UD90 1TB if msrp matters more to you.
| Spec | Silicon PowerUD90 1TB | Western DigitalWD Black SN850X 2TB |
|---|---|---|
| Storage | ||
| Capacity | 1000 GB | 2000 GB+100% |
| 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 | 4,800 MB/s | 7,300 MB/s+52% |
| Sequential Write | ||
| 4,200 MB/s |
| 6,600 MB/s+57% |
| Endurance (TBW) | 600 | 1,200+100% |
| Features | ||
| DRAM Cache | No | Yes+100% |
| Platform | ||
| Controller | Phison PS5021-E21T | WD in-house |
| PCIe Gen | 4 | 4 |
| Price | ||
| MSRP | $45−68% | $140 |
| Release Date | Mar 2023 | Aug 2022 |
