Samsung 990 EVO Plus vs WD_BLACK SN850X at every capacity: prices, $/TB, speeds, endurance. Which to buy in October 2026 — full family comparison.
Samsung 990 EVO Plus and WD_BLACK SN850X compete at every capacity where both are sold, so the real question isn't a single price tag — it's which family gives you more per terabyte at the capacity you actually need. The table below breaks that down.
Peak sequential read favors the WD_BLACK SN850X at 7,300 MB/s against 7,250 MB/s. For gaming and general desktop use the difference is imperceptible; for large-file work it's measurable.
The Samsung 990 EVO Plus family is the value pick — $167.25/TB at its cheapest configuration versus $175.00/TB for the WD_BLACK SN850X. The WD_BLACK SN850X has to win on features (cache, endurance, brand support) to justify its premium.
Architecturally, the WD_BLACK SN850X family uses a dedicated DRAM cache while the Samsung 990 EVO Plus relies on HMB (Host Memory Buffer). For OS and gaming duty they behave identically; sustained random writes favor DRAM.
| Capacity | Samsung 990 EVO Plus | WD_BLACK SN850X | |
|---|---|---|---|
| 1 TB | $237 · $237.00/TB | $248 · $248.00/TB | Full comparison → |
| 2 TB | $370 · $185.00/TB | $390 · $195.00/TB | Full comparison → |
| 4 TB | $669 · $167.25/TB | $700 · $175.00/TB | Full comparison → |
| 8 TB | — | $1750 · $218.75/TB |