Samsung 990 PRO 2TB ($388) vs WD_BLACK SN850X 4TB ($535). $/TB analysis, performance, and use-case recommendations.
Both run on Gen 4 hardware but at different capacities: 2 TB for the Samsung 990 PRO 2TB versus 4 TB for the WD_BLACK SN850X 4TB. Whether the larger drive's $/TB advantage justifies the higher upfront cost depends on how much you actually need.
Hardware-wise, the Samsung 990 PRO 2TB runs on the in-house Samsung Pascal — engineered specifically for the 990 PRO at 8nm. The WD_BLACK SN850X 4TB pairs WD's G2 controller — manufactured by SanDisk and tuned for low-latency gaming workloads.
The cost difference is hard to ignore: 31% per TB (WD_BLACK SN850X 4TB at $133.75/TB versus Samsung 990 PRO 2TB at $194.00/TB). Unless you specifically need the Samsung 990 PRO 2TB's peak performance, the WD_BLACK SN850X 4TB delivers more storage for the money.
WD_BLACK SN850X 4TB earns higher TBW ratings (2,400 vs 1,200 TBW) — relevant for sustained write workloads, irrelevant for everything else.
For PS5 expansion, both are PCIe Gen 4 M.2 2280 drives that meet Sony's minimum spec (7,300 MB/s read). The console can't take advantage of speeds beyond that, so save money by choosing the WD_BLACK SN850X 4TB. Note for handheld gamers: M.2 2280 is the desktop/laptop standard. Steam Deck and the ROG Ally line need 2230 drives — neither Samsung 990 PRO 2TB nor WD_BLACK SN850X 4TB fits without modification.
Market context: the Samsung 990 PRO 2TB ranks #10 of 11 Gen 4 2 TB drives we track by $/TB, while the WD_BLACK SN850X 4TB ranks #4 of 6 Gen 4 4 TB drives. Neither cracks the top of the value table, so it's worth glancing at the alternatives below before picking either.
The Samsung 990 PRO 2TB is the right call if the lower retail price ($388 vs $535) matter to you. Among consumer SSD makers, Samsung's PRO series consistently scores highest on long-term reliability surveys (Backblaze, Puget Systems Q1 2026 data).
The WD_BLACK SN850X 4TB is the right call if better $/TB economics ($133.75/TB), and a higher TBW endurance rating (2,400 TBW) matter to you. Among Gen 4 flagships, the SN850X strikes a sweet spot — premium silicon at sub-Samsung pricing, with WD's established RMA process to back it up.