WD Black SN850X 4TB
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Technical Specifications
Performance at a Glance
| Series | WD Black SN850X |
| Brand | Western Digital |
| Model | WD Black SN850X 4TB |
| Capacity | 4TB |
| Type | NVMe SSD |
| Interface | PCIe 4.0 x4 |
| Form Factor | M.2 2280 |
| Sequential Read | 7,300 MB/s |
| Sequential Write | 6,600 MB/s |
| TBW (Endurance) | 2,400 TBW |
| NAND Type | 3D TLC NAND |
| DRAM Cache | Yes - 4GB DDR4 |
| Warranty | 5 Years |
Overview
The 4TB SN850X uses a single-sided design despite the high capacity, which matters for laptop and PS5 compatibility. Performance is identical to the smaller models: 7,300 MB/s reads and 6,600 MB/s writes. The 2,400 TBW rating is overkill for most users, but if you need 4TB of fast NVMe storage in a single slot, this is a top choice.