Compare Samsung 990 PRO 2TB and WD_BLACK SN7100 4TB: prices, speeds, $/TB. Which to buy in May 2026? Full spec breakdown.
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 SN7100 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 Samsung's 8nm Pascal controller, the silicon powering the 990 PRO line. The WD_BLACK SN7100 4TB pairs SanDisk's A101 controller, used in newer WD_BLACK SKUs after the SanDisk spinoff.
Price separates these two meaningfully. The WD_BLACK SN7100 4TB costs $79.75/TB versus $109.50/TB for the Samsung 990 PRO 2TB — a 27% premium that needs justification in real benchmarks, not just spec-sheet bragging.
The Samsung 990 PRO 2TB carries a dedicated DRAM chip for FTL (Flash Translation Layer) mapping; the WD_BLACK SN7100 4TB relies on HMB (Host Memory Buffer), borrowing 64 MB from system RAM. The practical gap shows up only under sustained random write loads.
On warranty endurance the WD_BLACK SN7100 4TB carries 2,400 TBW against Samsung 990 PRO 2TB's 1,200 TBW. Both will outlast typical use, but the gap matters if you're doing professional content work.
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 SN7100 4TB wins this matchup on $/TB. Both drives use the 2280 form factor, which is too long for Steam Deck or ROG Ally — you'd need a 2230 variant if either manufacturer offers one, or a dedicated handheld-format drive instead.
Pick the Samsung 990 PRO 2TB if you value the lower retail price ($219 vs $319), and a dedicated DRAM cache chip. Samsung's PRO line has the longest track record for firmware reliability — over a decade of consumer SSDs with global RMA support.
Pick the WD_BLACK SN7100 4TB if you value better $/TB economics ($79.75/TB), and a higher TBW endurance rating (2,400 TBW).