SSD comparison · Updated May 14, 2026

WD_BLACK SN850X 2TB vs Lexar NM790 2TB

Side-by-side: WD_BLACK SN850X 2TB ($199) vs Lexar NM790 2TB ($149). $/TB winner, specs, real-world picks for May 2026.

WD_BLACK SN850X 2TB Gen 4

WD · WD G2
$199
$99.50/TB
View on Amazon →

Lexar NM790 2TB Gen 4

Lexar · MAP1602
$149
$74.50/TB
View on Amazon →
Generation
Gen 4
Gen 4
Price (USD)
$199
$149
Capacity
2 TB
2 TB
$/TB
$99.50
$74.50
Sequential read
7,300 MB/s
7,400 MB/s
Sequential write
6,600 MB/s
6,500 MB/s
Interface
PCIe 4.0 x4
PCIe 4.0 x4
Controller
WD G2
MAP1602
DRAM cache
Yes
No (HMB)
TBW endurance
1,200 TBW
1,500 TBW
Warranty
5 years
5 years
PS5 compatible
Yes
Yes

Verdict: WD_BLACK SN850X 2TB vs Lexar NM790 2TB

Gen 4 at 2 TB is one of the most contested SSD segments in 2026, and WD_BLACK SN850X 2TB versus Lexar NM790 2TB captures that competition well. The decision rarely comes down to peak speeds — both drives saturate typical workloads.

Hardware-wise, the WD_BLACK SN850X 2TB runs on the proprietary WD G2 silicon, optimized for the WD_BLACK line. The Lexar NM790 2TB pairs a MAP1602 controller built specifically for DRAM-less HMB designs.

Money matters here — $74.50/TB on the Lexar NM790 2TB versus $99.50/TB on the WD_BLACK SN850X 2TB. That's enough of a spread that for budget-conscious builders, the Lexar NM790 2TB becomes the default unless reviews of your specific workload prefer the WD_BLACK SN850X 2TB.

The DRAM-vs-HMB question divides opinion: WD_BLACK SN850X 2TB's on-board DRAM theoretically helps under sustained workloads, while Lexar NM790 2TB's HMB approach has matured enough that most users won't see the difference. Pick on price if everything else is similar.

Real-world use cases

For PS5 expansion, both are PCIe Gen 4 M.2 2280 drives that meet Sony's minimum spec (7,300 MB/s read). The console can't take advantage of speeds beyond that, so save money by choosing the Lexar NM790 2TB. Note for handheld gamers: M.2 2280 is the desktop/laptop standard. Steam Deck and the ROG Ally line need 2230 drives — neither WD_BLACK SN850X 2TB nor Lexar NM790 2TB fits without modification.

Pick the WD_BLACK SN850X 2TB if...

Go with the WD_BLACK SN850X 2TB for a dedicated DRAM cache chip. WD_BLACK's SN850X earned its reputation through consistent sustained performance under gaming workloads — fewer micro-stutters during open-world streaming than budget alternatives.

Pick the Lexar NM790 2TB if...

Go with the Lexar NM790 2TB for the lower retail price ($149 vs $199), and better $/TB economics ($74.50/TB). The Lexar NM790 2TB 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.

Best value for money

Lexar NM790 2TB
$74.50/TB beats the alternative by 25%

Best for gaming

Lexar NM790 2TB
Strong $/MB-s ratio for game loads, and fits the PS5 expansion slot

Best for content creators

WD_BLACK SN850X 2TB
Best write-heavy profile here: 6,600 MB/s sustained, 1,200 TBW

Best for PS5

Lexar NM790 2TB
PS5-compatible Gen 4 at $74.50/TB

WD_BLACK SN850X 2TB vs Lexar NM790 2TB — common questions

What's the price difference between WD_BLACK SN850X 2TB and Lexar NM790 2TB?

The Lexar NM790 2TB costs $149 (74.50 per TB), while the WD_BLACK SN850X 2TB runs $199 (99.50 per TB). The gap is $50, equivalent to about 25% per TB. Prices change weekly; check current Amazon listings before deciding.

Does the Lexar NM790 2TB's read advantage matter in practice?

Specs say yes (7,400 MB/s versus 7,300 MB/s). Real-world testing says rarely. Game load times and OS boots saturate well below either drive's peak read speed. The advantage shows up in sustained sequential reads — large file copies, raw video reads, dataset loads.

Will the WD_BLACK SN850X 2TB or Lexar NM790 2TB work in my PlayStation 5?

Yes to both — both meet Sony's expansion specs (PCIe Gen 4 NVMe, M.2 2280, with a heatsink). The PS5 won't differentiate between them in benchmarks because its internal storage controller throttles to PCIe Gen 4 speeds. Lexar NM790 2TB wins this matchup if price is your tiebreaker.

Does the WD_BLACK SN850X 2TB's DRAM cache make a noticeable difference?

For OS, gaming, and general productivity: no. The Lexar NM790 2TB's HMB (Host Memory Buffer) implementation matches DRAM performance within 5% on these workloads. DRAM matters for sustained random writes — databases, multi-GB file operations, video editing project saves. Heavy daily writers see the difference; casual users do not.

How much does the 300 TBW endurance gap actually matter?

For most buyers, it doesn't. The Lexar NM790 2TB's 1,500 TBW versus the WD_BLACK SN850X 2TB's 1,200 TBW translates to years of additional theoretical lifetime, but consumer drives almost always die from controller failure or firmware issues long before reaching TBW limits.

Bottom line: WD_BLACK SN850X 2TB or Lexar NM790 2TB?

Default recommendation: Lexar NM790 2TB. It hits the right balance of price ($74.50/TB), Gen 4 performance, and brand support for the average buyer. The WD_BLACK SN850X 2TB has its place if you need higher sustained write speeds, but that's a narrower use case.