Samsung 990 PRO 4TB ($825) vs WD_BLACK SN850X 8TB ($1300). $/TB analysis, performance, and use-case recommendations.
Both run on Gen 4 hardware but at different capacities: 4 TB for the Samsung 990 PRO 4TB versus 8 TB for the WD_BLACK SN850X 8TB. 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 4TB runs on Samsung's Pascal controller, fabricated on the company's 8nm process. The WD_BLACK SN850X 8TB pairs WD's second-generation G2 in-house controller, tuned for sustained gaming I/O.
The cheaper drive — WD_BLACK SN850X 8TB at $162.50/TB — saves you $43.75 per TB versus the Samsung 990 PRO 4TB. Worth it if you're capacity-constrained; either works if you just want one fast drive.
Endurance leans toward the WD_BLACK SN850X 8TB at 4,800 TBW (versus 2,400 TBW for the Samsung 990 PRO 4TB). For most consumers this never becomes a real concern — 600 TBW lasts a decade of normal writes — but heavy daily writers should weight it.
Heading to a PlayStation 5? Both drives drop into the console's M.2 bay and report identical real-world benchmarks since the PS5 caps storage at PCIe 4.0 speeds. The WD_BLACK SN850X 8TB wins this matchup on $/TB. Heads-up — these are full-length 2280 drives. Steam Deck and most current handhelds require shorter 2230 modules, so check capacity-specific 2230 variants if that's your target platform.
Market context: the Samsung 990 PRO 4TB ranks #6 of 6 Gen 4 4 TB drives we track by $/TB, while the WD_BLACK SN850X 8TB ranks #1 of 1 Gen 4 8 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 4TB is the right call if the lower retail price ($825 vs $1300) matter to you. Samsung backs the PRO series with one of the strongest warranty experiences in consumer storage — RMAs typically process within 5 business days globally.
The WD_BLACK SN850X 8TB is the right call if better $/TB economics ($162.50/TB), and a higher TBW endurance rating (4,800 TBW) matter to you. The SN850X has been the best-selling Gen 4 NVMe in PCPartPicker builds for two consecutive years — Game Mode 2.0 prioritizes I/O when supported titles need it.