SSD family comparison · Updated October 19, 2026 · Prices verified October 19, 2026

WD Blue SN5100 vs WD_BLACK SN850X

WD Blue SN5100 vs WD_BLACK SN850X at every capacity: prices, $/TB, speeds, endurance. Which to buy in October 2026 — full family comparison.

Verdict: WD Blue SN5100 vs WD_BLACK SN850X

WD Blue SN5100 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 6,600 MB/s. For gaming and general desktop use the difference is imperceptible; for large-file work it's measurable.

The WD Blue SN5100 family is the value pick — $167.00/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.

The cache design differs: WD_BLACK SN850X carries on-board DRAM, WD Blue SN5100 borrows system RAM via HMB. This matters for database-style workloads and long video-editing sessions, not for everyday use.

WD Blue SN5100 vs WD_BLACK SN850X: price by capacity

Capacity	WD Blue SN5100	WD_BLACK SN850X
1 TB	$167 · $167.00/TB	$248 · $248.00/TB	Full comparison →
2 TB	—	$390 · $195.00/TB
4 TB	—	$700 · $175.00/TB
8 TB	—	$1750 · $218.75/TB

Spec comparison (1 TB models)

Generation

Gen 4

Interface

PCIe 4.0 x4

Sequential read

6,600 MB/s

7,300 MB/s

Sequential write

5,400 MB/s

6,300 MB/s

Controller

SanDisk

WD G2

DRAM cache

No (HMB)

Yes

Warranty

5 years

PS5 compatible

Yes

FAQ

WD Blue SN5100 vs WD_BLACK SN850X — common questions

Which is cheaper per TB, WD Blue SN5100 or WD_BLACK SN850X?

As of October 19, 2026, the WD Blue SN5100 family offers the better $/TB: its best configuration is $167.00/TB versus $175.00/TB for the WD_BLACK SN850X. The exact winner varies by capacity — see the capacity table for per-size pricing.

Which capacity of the WD Blue SN5100 or WD_BLACK SN850X should I buy?

2 TB is the sweet spot for most builds: better $/TB than 1 TB and better availability than 4 TB+ during the 2026 NAND shortage. Check the capacity table above — the per-TB winner can flip between capacities.

Are the WD Blue SN5100 and WD_BLACK SN850X PS5 compatible?

Both families are PCIe NVMe M.2 2280 and work in the PS5 expansion slot. The PS5 caps sustained speeds at ~5,500 MB/s, so pick on price, not peak speed, and add a heatsink.