Lexar LNM620

1. Product Overview and Market Positioning

The Lexar NM620 (model variants: LNM620X001T-RNNNU for 1TB) is a PCIe Gen3 x4 NVMe SSD launched in March 2021, targeting budget-conscious gamers, content creators, and PC upgraders. Positioned as an entry-level performance drive, it promises sequential speeds up to 3,300 MB/s read and 3,000 MB/s write (for 1TB/2TB models), leveraging NVMe 1.4 technology and 3D TLC NAND.

2. Technical Specifications

Core Hardware

• Controller: InnoGrit IG5216 (Shasta+), rebranded as Lexar DM620 512.

• NAND Flash: Micron 96-layer 3D TLC (B27B FortisFlash) or YMTC TLC variants .

• Form Factor: M.2 2280 (single-sided design) .

• Capacities: 256GB, 512GB, 1TB, 2TB .

• Interface: PCIe 3.0 x4 (NVMe 1.4) .

Performance Metrics

Table: Performance by Capacity 15

Endurance and Reliability

• Endurance: Modest for TLC NAND (e.g., 500TBW for 1TB vs. 600TBW for WD Blue SN550) .

• Warranty: 5-year limited .

• Error Correction: LDPC (Low-Density Parity Check) for data integrity .

• Durability: Shock-resistant (1,500G) and vibration-resistant (20G) .

3. Performance Deep Dive

Strengths

• Sequential Speeds: Near-advertised read/write in CrystalDiskMark (e.g., 3,223 MB/s read, 2,301 MB/s write for 512GB) .

• SLC Cache: Dynamic ~208GB cache (1TB model) absorbs bursts; initial writes hit 2.5 GB/s before dropping .

• 4K Writes: Competent random write performance (256K IOPS) 6.

• Real-World Use: Handles game loads and OS boot efficiently; 6× faster than SATA SSDs .

Weaknesses

• Sustained Writes: Post-cache speeds plummet to 800 MB/s (average), collapsing to 140–190 MB/s under heavy loads

• Random I/O: Poor 4K random read (82K IOPS) and VDI benchmarks (25K IOPS in boot tests) .

• PCMark 10: Subpar scores in trace-based tests (e.g., Call of Duty load times) .

• Houdini Rendering: Slow CGI workloads (3,577 seconds vs. competitors’ sub-1,000) .

4. Thermal and Power Efficiency

• Thermals: Idle at 30–40°C; peaks at 89°C during writes (thermal imaging). Minimal throttling with airflow .

• Power Management: Optimized for laptops; 20–30% lower consumption vs. HDDs .

• No Heatsink: Bare PCB design risks throttling in cramped laptops; users should add thermal pads .

5. Endurance and Reliability Concerns

• Low TBW: 500TBW for 1TB (0.44 DWPD) trails rivals (e.g., Samsung 980: 600TBW) .

• NAND Quality: Micron B27B TLC rated for 3,000 P/E cycles (conservative vs. industry avg) .

• No Encryption: Lacks hardware AES encryption .

6. Value Proposition and Competition

Pricing (2025 Refurbished Market)

Competitive Landscape

• WD Blue SN550: Better sustained writes (1.5 GB/s) and endurance at similar pricing .

• Samsung 980: Superior random I/O and 13¢/GB value.

• Intel 670p (QLC): Comparable endurance but weaker writes .

Target Audience

• Budget Gamers: Adequate for game libraries (fast load times in SLC cache) .

• Casual Users: Office tasks, web browsing, light content creation .

• Avoid For: 4K video editing, database workloads, or sustained write scenarios .

7. Controversies and Hardware Variants

• Inconsistent Performance: Users report drastic speed variances (e.g., 3,481 MB/s read vs. 850 MB/s in professional tests) due to:

  • NAND/Controller Mix: Micron/YMTC flash and MAP1202/IG5216 controllers 512.

  • Firmware Issues: Early revisions (V1.8) had optimization flaws 6.

• “Spectacular Fail” Claims: StorageReview dubbed it a failure for intensive workloads after ranking last in 9/10 benchmarks .

8. Verdict: A Budget Warrior with Caveats

The Lexar NM620 excels as a cost-effective upgrade from SATA SSDs or HDDs, delivering solid sequential speeds and solid burst performance for casual use. Its 5-year warranty and shock resistance add reliability points. However, severe limitations in sustained writes, random I/O, and endurance make it unsuitable for professional workloads.