Overview

The WD Black SN850X is Western Digital’s premier gaming-focused NVMe SSD, delivering sequential read speeds up to 7,300 MB/s and write speeds up to 6,600 MB/s. Launched in May 2022, it builds on the SN850 with higher capacities up to 8TB and exclusive Game Mode 2.0 features. The drive uses Kioxia 112-layer BiCS5 TLC NAND paired with WD’s custom Black G2 controller for exceptional gaming and content creation performance. It competes directly with the Samsung 990 Pro (7,450 MB/s reads) and the Seagate FireCuda 530 (7,300 MB/s), but sets itself apart with Game Mode 2.0’s Predictive Loading and the unique 8TB capacity option that no rival currently offers.

Design & Build

The SN850X adopts the standard M.2 2280 form factor with a single-sided design for most capacities, though the 4TB variant uses a double-sided PCB. A version with an integrated heatsink is available featuring RGB lighting controlled via WD’s Dashboard software. The drive includes WD’s Adaptive Thermal Management to prevent throttling during sustained workloads. Build quality is robust, and the black PCB with clean component layout reflects the product’s premium positioning.

Performance

In benchmarks, the SN850X achieves 7,300 MB/s sequential reads and 6,600 MB/s sequential writes, placing it among the fastest PCIe 4.0 drives. Random performance reaches 1.2 million IOPS read and 1.1 million IOPS write. Game Mode 2.0 includes Predictive Loading that pre-loads game assets for up to 15% faster level transitions in supported titles. Large file transfers of 100GB maintain speeds above 3,000 MB/s throughout thanks to a 600GB SLC cache on the 2TB model.

Features

The WD Black Dashboard software is the control center, offering drive health monitoring, firmware updates, and RGB customization on heatsink models. Game Mode 2.0 adds Predictive Loading to anticipate data needs, Overhead Balancing to manage multi-queue operations, and Automatic Thermal Management to maintain peak performance. The drive supports Microsoft DirectStorage for reduced CPU utilization and faster load times in compatible games.

Pros

• Excellent sequential (7,300 MB/s) and random 4K (1.2M IOPS read) performance, among the fastest PCIe 4.0 drives
• Game Mode 2.0 with Predictive Loading technology for up to 15% faster level transitions
• Available in capacities up to 8TB - unique in the consumer PCIe 4.0 market
• Optional RGB heatsink version for showcase gaming builds
• Strong 5-year warranty with 600 TBW per TB endurance rating
• 600 GB SLC cache on 2TB model maintains >3,000 MB/s writes during sustained transfers

Cons

• PCIe 4.0 only, no Gen 5 support on this model; next-gen SN8100 already offers Gen 5 speeds
• Heatsink version is thicker (single-sided) and may not fit all laptops or PS5 clearance
• Dashboard software is Windows-only - no macOS or Linux utility for drive management
• Premium price per gigabyte versus competitors (Samsung 990 Pro is often $10-20 less for equivalent capacity)

Verdict

The WD Black SN850X is an exceptional gaming SSD that delivers top-tier PCIe 4.0 performance with thoughtful gaming-centric features. Its high capacity options and Game Mode 2.0 make it the go-to choice for serious gamers building high-end rigs.

Sources

• Western Digital - WD_BLACK SN850X NVMe SSD
• WD - SN850X Official Datasheet (PDF)
• StorageReview - WD Black SN850X SSD Review
• Dong Knows Tech - WD Black SN850X Review