Compare Samsung 990 PRO 4TB and Lexar NM790 4TB: prices, speeds, $/TB. Which to buy in July 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 Pascal controller, fabricated on the company's 8nm process. The Lexar NM790 4TB pairs the MaxioTech MAP1602 — a DRAM-less Gen 4 controller dominating the value tier across TeamGroup, Lexar, and others.
Price separates these two meaningfully. The Lexar NM790 4TB costs $127.50/TB versus $206.25/TB for the Samsung 990 PRO 4TB — a 38% 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.
For PlayStation 5 builds, the console's internal M.2 slot tops out around 5,500 MB/s sustained, so both Samsung 990 PRO 4TB and Lexar NM790 4TB hit the same wall — pick whichever is cheaper at the moment you buy. 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: we track 6 Gen 4 4 TB drives, and by price per terabyte the Samsung 990 PRO 4TB currently sits #6 while the Lexar NM790 4TB sits #1. That puts at least one of them near the top of the value table — a reasonable head-to-head to be choosing from.
At $127.50/TB, the Lexar NM790 4TB is already among the cheapest 4 TB drives we track — nothing in this class undercuts it. See the full $/TB ranking.
Pick the Samsung 990 PRO 4TB if you value a dedicated DRAM cache chip. Samsung backs the PRO series with one of the strongest warranty experiences in consumer storage — RMAs typically process within 5 business days globally.
Pick the Lexar NM790 4TB if you value the lower retail price ($510 vs $825), and better $/TB economics ($127.50/TB). The Lexar NM790 4TB wins on $/TB because it pairs DRAM-less MAP1602 silicon with low-margin distribution. Performance is fine for OS and gaming, weaker only on sustained random writes.