Western Digital WD_BLACK SN850P 4TB
4TB · M.2 2280 · PCIe 4.0 x4
Specifications
Yes
DRAM cache
7300 MB/s
Sequential read
6600 MB/s
Sequential write
2400 TBW
Endurance
Family guide
WD_BLACK NVMe SSDs| SN770 | SN850X | SN850P This model | SN7100 | SN8100 | |
|---|---|---|---|---|---|
| Released | 2022 | 2022 | 2023 | 2024 | 2025 |
| Interface | Not available | PCIe 4.0 x4 | PCIe 4.0 x4 | PCIe 4.0 x4 | PCIe 5.0 x4 |
| Read | Not available | 7300 MB/s | 7300 MB/s | 7000 MB/s | 14900 MB/s |
| Write | Not available | 6600 MB/s | 6600 MB/s | 6700 MB/s | 14000 MB/s |
| Endurance | Not available | 2400 TBW | 2400 TBW | 2400 TBW | 2400 TBW |
| Summary | DRAM-less: it borrows system memory (HMB) instead, which the PS5 doesn't support, so console speeds may fall short. | WD_BLACK's flagship PCIe 4.0 drive, with a DRAM cache that the SN770 and SN7100 lack. | Same drive as the SN850X, sold only with a heatsink and licensed for the PS5. | DRAM-less successor to the SN770, with newer TLC flash and better power efficiency. | Has a DRAM cache and draws little power for its speed, but can still run hot without a heatsink. |
Capacity grid
| 250GB | 500GB | 1TB | 2TB | 4TB | 8TB | |
|---|---|---|---|---|---|---|
| SN770 | No listings | $239.28 | $179.14 | $379.99 | Not available | Not available |
| SN850X | Not available | Not available | $229.99 | $373.99 | $729.97 | $1,699 |
| SN850P | Not available | Not available | $240 | $419.98 | Out of stock This model | $1,649.97 |
| SN7100 | Not available | $159.99 | $169.99 | $319 | $629.99 | Not available |
| SN8100 | Not available | Not available | $269.99 | $399 | $759 | $1,699 |
How it compares
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Price history
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