Samsung 990 PRO 1TB ($135) vs Lexar NM790 4TB ($269). $/TB analysis, performance, and use-case recommendations.
Both run on Gen 4 hardware but at different capacities: 1 TB for the Samsung 990 PRO 1TB versus 4 TB for the Lexar NM790 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 1TB runs on the in-house Samsung Pascal — engineered specifically for the 990 PRO at 8nm. The Lexar NM790 4TB pairs a MAP1602 controller built specifically for DRAM-less HMB designs.
The cost difference is hard to ignore: 50% per TB (Lexar NM790 4TB at $67.25/TB versus Samsung 990 PRO 1TB at $135.00/TB). Unless you specifically need the Samsung 990 PRO 1TB's peak performance, the Lexar NM790 4TB delivers more storage for the money.
Cache architecture differs: Samsung 990 PRO 1TB has DRAM hardware, Lexar NM790 4TB uses HMB. For OS, gaming, browsing — indistinguishable. For databases, large file ops, or 4K video editing — DRAM has a small but consistent edge.
Lexar NM790 4TB earns higher TBW ratings (3,000 vs 600 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 (7,400 MB/s read). The console can't take advantage of speeds beyond that, so save money by choosing the Lexar NM790 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 1TB nor Lexar NM790 4TB fits without modification.
The Samsung 990 PRO 1TB is the right call if the lower retail price ($135 vs $269), and a dedicated DRAM cache chip 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 Lexar NM790 4TB is the right call if better $/TB economics ($67.25/TB), and a higher TBW endurance rating (3,000 TBW) matter to you. The Lexar NM790 4TB captures the value tier well: same NAND class as flagships, paired with a DRAM-less controller that costs less and uses HMB for the address-mapping table.