Compare Samsung 990 PRO 4TB and Lexar NM790 4TB: prices, speeds, $/TB. Which to buy in May 2026? Full spec breakdown.
Both the Samsung 990 PRO 4TB and Lexar NM790 4TB sit in the Gen 4 category at 4 TB, so the matchup turns on controller efficiency, cache topology, and current pricing rather than raw class differences.
Hardware-wise, the Samsung 990 PRO 4TB runs on Samsung's 8nm Pascal controller, the silicon powering the 990 PRO line. The Lexar NM790 4TB pairs MaxioTech's MAP1602 silicon, the default choice for budget Gen 4 drives in 2024-2026.
Price separates these two meaningfully. The Lexar NM790 4TB costs $67.25/TB versus $97.25/TB for the Samsung 990 PRO 4TB — a 31% premium that needs justification in real benchmarks, not just spec-sheet bragging.
The Samsung 990 PRO 4TB carries a dedicated DRAM chip for FTL (Flash Translation Layer) mapping; the Lexar NM790 4TB relies on HMB (Host Memory Buffer), borrowing 64 MB from system RAM. The practical gap shows up only under sustained random write loads.
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 Lexar NM790 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 4TB if you value 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 Lexar NM790 4TB if you value the lower retail price ($269 vs $389), and better $/TB economics ($67.25/TB). Budget-tier drives like the Lexar NM790 4TB have closed the gap with premium NVMes — the MAP1602 controller is genuinely competitive for everyday workloads at half the price.