Western Digital Black SN770M Review

The explosive growth of handheld PC gaming has created a new, insatiable demand for storage that is both tiny and fast. Western Digital’s Black SN770M steps directly into this arena, promising a no-compromise upgrade for devices where every millimeter counts.

The WD Black SN770M is an answer to a very specific, yet increasingly common, problem: the limited internal storage of today’s powerful handheld gaming PCs and ultra-thin laptops. Built on the diminutive M.2 2230 “gumstick” form factor, it’s designed to be a drop-in replacement for the stock drives in devices like the Steam Deck, ASUS ROG Ally, and certain Microsoft Surface models. While other brands have catered to this niche, the entry of a heavyweight like Western Digital brings a welcome dose of brand recognition and reliability to the market.

Performance in a Tiny Package

Don’t let its size fool you; this is a proper PCIe 4.0 NVMe SSD. Leveraging a DRAM-less architecture that uses Host Memory Buffer (HMB) to keep costs and power consumption down, the SN770M punches well above its weight. Western Digital quotes sequential read speeds up to 5,150 MB/s, and in real-world use, it delivers a transformative experience compared to the stock drives in many handhelds. Game loading times are slashed, system responsiveness feels snappier, and large file transfers complete in a fraction of the time. While it won’t challenge the top-tier M.2 2280 drives you’d put in a high-end desktop, that’s not its mission. For its intended purpose—accelerating a portable gaming machine—the performance is stellar and more than enough to saturate the capabilities of current handheld CPUs.

Design and Compatibility

The physical design is arguably its most important feature. The SN770M is a single-sided drive, meaning all the NAND chips and the controller are on one side of the PCB. This is a critical detail for ensuring compatibility in the incredibly tight confines of a Steam Deck or ROG Ally, where a double-sided drive simply will not fit. The build quality is standard for a WD Black product, featuring the clean, professional aesthetic the line is known for. Installation is straightforward for anyone comfortable opening up their device, making this one of the simplest and most effective upgrades you can perform.

Value and the Competition

This is where the conversation gets nuanced. M.2 2230 drives carry a significant price premium over their larger M.2 2280 counterparts due to the manufacturing complexity and lower production volume. The SN770M is competitively priced within its niche but is undoubtedly an expensive purchase when viewed purely on a cost-per-gigabyte basis against standard SSDs. However, the value proposition isn’t just about raw capacity. It’s about unlocking the full potential of a multi-hundred-dollar handheld device, eliminating storage anxiety, and getting that performance from a Tier-1 brand with a strong warranty and supporting software like the WD Dashboard.

Ultimately, the WD Black SN770M is a premium solution for a specific need. For handheld gamers who have felt the squeeze of a 64GB or 512GB stock drive, this SSD is a godsend. It provides the speed and capacity to load up a device with a substantial library of AAA titles without compromise. While it demands a premium, the seamless performance uplift and the peace of mind that comes with a trusted brand make it a very compelling choice for those looking to supercharge their portable powerhouse.

Where to Buy:

Check it out on Amazon