Lexar NM620 1TB NVMe SSD Review (2026)
The Lexar NM620 1TB is the flagship of the NM620 line — a DRAM-less PCIe 3.0 NVMe drive that delivers 3,300/3,000 MB/s sequential speeds and 500 TBW endurance under a five-year warranty.
Controller & Memory
The NM620 1TB uses the Lexar DM620 controller paired with four Micron 96-layer 3D TLC NAND packages on a single-sided M.2 2280 PCB. Being DRAM-less, it relies on the NVMe HMB (Host Memory Buffer) feature to maintain its flash translation layer in host system memory. The drive supports NVMe 1.4 over a PCIe 3.0 x4 interface.
This is the only NM620 capacity that reaches the full 3,000 MB/s rated write speed — the 512GB drops to 2,400 MB/s and the 256GB to just 1,300 MB/s. The 1TB also benefits from a larger SLC write cache, which independent reviewers found holds roughly 200 GB before dropping to native TLC write speeds around 800 to 900 MB/s. Endurance sits at 500 TBW, which is 0.44 drive writes per day over five years.
In the mainstream DRAM-less segment, the NM620 1TB competes against the WD Blue SN550 1TB, Crucial P2 1TB, and Samsung 980 1TB. The Samsung 980 leads in PCMark real-world benchmarks, while the NM620 trades blows in CrystalDiskMark synthetic tests and often undercuts on price.
Storage Comparisons:
NM620 Performance & Benchmarks
Lexar rates the NM620 1TB at up to 3,300 MB/s sequential reads and 3,000 MB/s sequential writes, with random performance up to 300,000 read IOPS and 256,000 write IOPS. In The PC Enthusiast's testing, ATTO measured approximately 3,000 MB/s reads but only about 2,100 MB/s writes — notably below the rated figure. CrystalDiskMark results were closer to spec.
Lexar NM620 1 TB vs M.2 3.0 x 4 peers
Switch between sequential throughput and random IOPS to see how this drive stacks up against other M.2 3.0 x 4 SSDs in our database. The highlighted bar is the drive on this page — click any other bar to open that drive.
- ADATA SX 8800 Pro 512 GB: 3,500 MB/s read, 2,700 MB/s write
- ADATA SX 8800 Pro 1 TB: 3,500 MB/s read, 2,700 MB/s write
- ADATA XPG Spectrix S40G RGB 256 GB: 3,500 MB/s read, 3,000 MB/s write
- ADATA XPG Spectrix S40G RGB 512 GB: 3,500 MB/s read, 3,000 MB/s write
- Lexar NM620 1 TB (this drive): 3,300 MB/s read, 3,000 MB/s write
A 310 GB real-world file copy test from a Samsung 980 Pro showed initial write speeds bouncing between 1.6 and 2.2 GB/s, then settling to roughly 840 to 890 MB/s after about 200 GB — consistent with SLC cache exhaustion. In PCMark 10 Full System Drive testing, the NM620 1TB outperformed the Crucial P2 but trailed both the WD Blue SN550 and Samsung 980. The 4K random write score in CrystalDiskMark was a bright spot, beating several direct competitors.
For daily desktop use and gaming, the NM620 1TB delivers speeds that any user upgrading from SATA will notice immediately. The gap to higher-priced drives only becomes apparent in sustained workloads or synthetic trace benchmarks.
Lexar NM620 vs Competitors
See how the NM620 stacks up against other M.2 3.0 x 4 drives in our database:
Compare with rival drives:
Endurance, TBW & Warranty
The Lexar NM620 1TB carries a 500 TBW endurance rating backed by a five-year limited warranty. That translates to approximately 274 GB of writes per day over the warranty period, or about 0.44 drive writes per day — a workload level that only heavy content creators approach. The drive is rated at 1.5 million hours MTBF. The five-year term is a meaningful upgrade over the three-year warranty on the older Lexar NM610, and no product registration is required to claim the full warranty period.
Lexar NM620 1 TB Specifications
| Category | Value |
|---|---|
| Capacity [?] | 1 TB |
| Interface [?] | M.2 3.0 x 4 |
| Controller [?] | Lexar DM620 |
| Memory type [?] | 3D TLC |
| DRAM [?] | HMB |
| Read speed (MB/s) [?] | 3300 |
| Write speed (MB/s) [?] | 3000 |
| Read IOPS [?] | 300000 |
| Write IOPS [?] | 256000 |
| Endurance (TBW) [?] | 500 |
| MTBF (million hours) [?] | 1.5 |
| Warranty (years) [?] | 5 |
Verdict: Is the NM620 Worth It in 2026?
The Lexar NM620 1TB is a solid mainstream NVMe SSD for everyday desktop use, gaming, and light content work. Its five-year warranty and 500 TBW endurance are competitive for the price. Buyers who prioritize top-tier real-world application performance should look to the Samsung 980 1TB, which consistently posts higher PCMark scores. Those who want the longest warranty at the lowest price will find the NM620 a pragmatic pick — just do not expect it to match its own 3,000 MB/s write rating outside of ideal synthetic conditions.
+ Pros
- 3,300 MB/s reads, 3,000 MB/s rated writes on PCIe 3.0
- 500 TBW endurance with five-year warranty
- Single-sided M.2 2280 fits laptops and slim desktops
- Strong 4K random write performance
- NVMe 1.4 with HMB support
- SLC cache holds roughly 200 GB before throttling
- Cons
- Real-world write speeds fall short of the 3,000 MB/s rating
- Trails Samsung 980 in PCMark trace benchmarks
- DRAM-less design limits heavy-workload performance
- No bundled software or heatsink included
Buy this or similar SSD Storage:
Video Review
Lexar NM620 M 2 2280 PCIe Gen3x4 NVMe SSD introduced by Squirrel Mark
