Compare WD_BLACK SN8100 2TB and Lexar NM790 2TB: prices, speeds, $/TB. Which to buy in July 2026? Full spec breakdown.
WD_BLACK SN8100 2TB vs Lexar NM790 2TB pits two different generations against each other at 2 TB. The question isn't which is faster on paper — that's settled — it's whether the bandwidth gap shows up in your specific workload.
Hardware-wise, the WD_BLACK SN8100 2TB runs on the SMI SM2508 — a 6nm Gen 5 controller running notably cooler than first-gen Phison E26 designs. The Lexar NM790 2TB pairs MaxioTech's MAP1602 silicon, the default choice for budget Gen 4 drives in 2024-2026.
There's a modest pricing advantage for the Lexar NM790 2TB: $155.00/TB compared with $190.00/TB. For typical gaming and productivity, this becomes the deciding factor when specs are close.
Read speeds favor the WD_BLACK SN8100 2TB: 14,900 MB/s versus 7,400 MB/s for the Lexar NM790 2TB, a 50% advantage. Sequential-heavy workloads notice; transactional workloads don't.
The WD_BLACK SN8100 2TB writes about 41% faster (11,000 MB/s vs 6,500 MB/s). Whether that matters depends entirely on what you write to the drive — gameplay capture and large project saves benefit, browsing and gaming do not.
The WD_BLACK SN8100 2TB carries a dedicated DRAM chip for FTL (Flash Translation Layer) mapping; the Lexar NM790 2TB relies on HMB (Host Memory Buffer), borrowing 64 MB from system RAM. The practical gap shows up only under sustained random write loads.
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 2TB. The leap from Gen 4 to Gen 5 doubles peak throughput on paper but produces single-digit-percent improvements in game load times, OS boot, and most productivity benchmarks. The Lexar NM790 2TB is the better default unless you have a specific workload that needs the extra lanes. Heavy write workloads — video editing, RAW photo libraries, backup operations — favor the WD_BLACK SN8100 2TB's 11,000 MB/s sustained write speed. 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.
Market context: the WD_BLACK SN8100 2TB ranks #5 of 11 Gen 5 2 TB drives we track by $/TB, while the Lexar NM790 2TB ranks #7 of 11 Gen 4 2 TB drives. Neither is a value leader right now — if $/TB is your priority, check the cheaper alternatives below before committing.
As of July 27, 2026, these tracked drives undercut both the WD_BLACK SN8100 2TB and Lexar NM790 2TB on $/TB:
Pick the WD_BLACK SN8100 2TB if you value meaningfully faster reads (14,900 MB/s), higher sustained writes (11,000 MB/s), and a dedicated DRAM cache chip.
Pick the Lexar NM790 2TB if you value the lower retail price ($310 vs $380), and better $/TB economics ($155.00/TB). Budget-tier drives like the Lexar NM790 2TB have closed the gap with premium NVMes — the MAP1602 controller is genuinely competitive for everyday workloads at half the price.