SanDisk WD_BLACK SN850P Review

Introduction

If you're a PlayStation 5 owner tired of the console's storage shuffle dance, the WD_BLACK SN850P NVMe SSD promises to end that frustration with official Sony blessing and a heatsink that bears the PlayStation logo. This PCIe Gen 4 drive targets PS5 gamers specifically, though it works equally well in gaming PCs that need a mid-range Gen 4 solution. Western Digital positioned this as the hassle-free expansion option for console players who want plug-and-play simplicity without researching compatibility requirements or shopping for aftermarket cooling solutions. With capacities ranging from one terabyte all the way to an impressive eight terabytes and speeds that meet Sony's demanding specifications, the SN850P sits in the sweet spot between budget Gen 3 drives and bleeding-edge Gen 5 performance. The real question isn't whether it works with your PS5, since Sony's official licensing guarantees compatibility, but whether this drive delivers better value than competing Gen 4 options that cost less but require separate heatsink purchases.

Product Overview

The WD_BLACK SN850P arrives in the standard M.2 2280 form factor that fits both PlayStation 5 expansion slots and most modern motherboards, measuring precisely 80mm in length, 24.46mm in width, and 9.89mm in total height with the integrated heatsink attached. Western Digital built this drive around their proprietary Black G2 controller, specifically the 20-82-20035-B2 variant that powers their SN850X line as well, paired with 112-layer TLC NAND flash memory manufactured by Kioxia. The presence of DRAM cache, which acts as a high-speed buffer for frequently accessed data and improves random access performance, distinguishes this from cheaper DRAMless competitors that rely entirely on Host Memory Buffer allocation from your system's RAM. The integrated heatsink features an exclusive PlayStation-branded design with Sony's logo prominently displayed, constructed from aluminum with thermal pads that make direct contact with the controller and NAND chips to dissipate heat during sustained gaming sessions.

Capacity options span from one terabyte through two terabytes, four terabytes, and up to eight terabytes, giving PS5 owners enough room to store anywhere from roughly 25 games on the smallest model to 200 games on the largest configuration based on average game sizes around 36GB. The PCIe 4.0 x4 interface provides backward compatibility with PCIe 3.0 systems, though you'll sacrifice roughly half the theoretical bandwidth when installed in older motherboards or enclosures. Western Digital rates the drive's endurance at 600 TBW for the one terabyte model, 1,200 TBW for two terabytes, 2,400 TBW for four terabytes, and an impressive 4,800 TBW for the flagship eight terabyte variant, with all capacities backed by Western Digital's five-year limited warranty that expires either after five years or when you exceed the rated TBW limit, whichever comes first.

Performance & Real World Speed

Western Digital specifies the SN850P at up to 7,300 MB/s sequential read speeds for the one terabyte through four terabyte models, with the eight terabyte model slightly slower at up to 7,200 MB/s reads. Sequential write performance varies by capacity, with the one terabyte model rated for up to 6,300 MB/s writes while the two terabyte, four terabyte, and eight terabyte configurations achieve up to 6,600 MB/s. These speeds place the SN850P firmly in flagship Gen 4 territory, matching or slightly trailing competitors like the Samsung 990 Pro and Crucial P5 Plus that occupy the same performance tier.

For PlayStation 5 gamers, these specifications translate to load times that essentially match the console's internal SSD, meaning you won't experience any performance degradation when launching games stored on the expansion drive versus those on the built-in storage. Titles like Spider-Man Miles Morales, Ratchet & Clank Rift Apart, and Horizon Forbidden West load within seconds, with fast travel sequences that previously required 30-45 seconds on external USB drives now completing in under 10 seconds. The drive fully supports Sony's DirectStorage implementation that streams game assets directly from the SSD to the GPU without taxing the CPU, maintaining the seamless world-loading technology that defines the PS5 experience.

PC gamers installing the SN850P in their rigs can expect Windows boot times around 10-15 seconds on clean installations, with application launches that feel nearly instantaneous for most software. Large file transfers like copying a 100GB game folder from another drive complete in roughly 90 seconds at the drive's rated sequential write speeds, though sustained writes beyond the SLC cache will see performance dip to approximately 1,500 MB/s once the cache fills on the one terabyte and two terabyte models. Random read and write performance, which matters more for everyday computing tasks than sequential speeds, reaches up to 800,000 IOPS for random reads on the one terabyte model and up to 1,200,000 IOPS on larger capacities, ensuring snappy system responsiveness even during multitasking scenarios.

Independent testing has shown that the SN850P sometimes falls slightly short of its rated speeds in real-world scenarios, with PlayStation 5 benchmarks occasionally reporting read speeds around 6,300 MB/s rather than the advertised 7,300 MB/s. This variance likely stems from thermal constraints within the PS5's enclosed M.2 bay and firmware variables, but the performance difference remains imperceptible during actual gaming since even 6,300 MB/s far exceeds Sony's minimum 5,500 MB/s requirement.

Thermal Management

PCIe Gen 4 NVMe drives generate substantial heat during operation, with controller temperatures easily reaching 70-80 degrees Celsius under sustained workloads, and the SN850P addresses this reality with an integrated heatsink specifically engineered for the PlayStation 5's tight dimensional constraints. The aluminum heatsink measures 9.89mm in total height, staying well within Sony's 11.25mm maximum clearance specification while providing adequate surface area for passive cooling through natural convection within the console's M.2 bay. Thermal pads make direct contact with both the controller chip and NAND packages, conducting heat away from these components and spreading it across the heatsink's fins for dissipation.

For PlayStation 5 installation, this integrated heatsink isn't just a convenience but a mandatory requirement since Sony's firmware will refuse to recognize and format any M.2 drive installed without adequate cooling. The SN850P's PlayStation-branded heatsink eliminates the compatibility guesswork that plagues generic Gen 4 drives, where users must either purchase separate heatsinks and hope they fit within Sony's strict dimensional limits or risk thermal throttling if the cooling solution proves inadequate. Western Digital's exclusive design accounts for the PS5's particular airflow characteristics, positioning thermal mass where the console's cooling system can work most effectively.

PC users installing the SN850P in their motherboards should verify clearance before purchase, particularly if installing in the M.2 slot positioned directly beneath a graphics card where vertical space becomes constrained. Most modern motherboards include their own M.2 heatsinks, and while you could theoretically remove the SN850P's integrated cooling to use your motherboard's solution instead, doing so voids Western Digital's warranty and eliminates the drive's official PlayStation 5 compatibility if you later decide to transfer it to your console. The heatsink's relatively low profile means it clears most motherboard-supplied M.2 covers, though you may need to remove your board's heatsink and rely solely on the SN850P's integrated cooling depending on your specific motherboard model.

Under sustained write workloads like copying large game libraries or recording gameplay footage, the SN850P maintains consistent performance without significant thermal throttling thanks to the heatsink's effectiveness. Controller temperatures typically stabilize around 65-75 degrees Celsius during heavy use, well within the drive's rated operational temperature range of 0-85 degrees Celsius. This thermal stability ensures that the drive won't suddenly slow to a crawl mid-download like some DRAMless competitors that lack both adequate cooling and thermal management firmware.

Compatibility

The WD_BLACK SN850P meets all of Sony's requirements for PlayStation 5 internal expansion, including the PCIe 4.0 NVMe interface, M.2 2280 form factor, sequential read speeds exceeding 5,500 MB/s, and integrated heatsink within dimensional specifications. Sony's firmware version 23.02-08.00.00 or higher supports the drive, and installation follows the straightforward process documented in PlayStation's official expansion guide involving removing the console's side panel, unscrewing the M.2 bay cover, inserting the drive into the slot, and securing it with the included mounting screw. Once installed, the PS5 automatically detects the drive during the next boot sequence and prompts you to format it for game storage, after which it appears as additional capacity in your storage management settings where you can choose default installation locations and move games between the internal SSD and expansion drive.

The SN850P is explicitly NOT compatible with Xbox Series X or Series S internal storage expansion, since Microsoft requires proprietary Seagate Storage Expansion Cards that connect via the console's dedicated expansion slot rather than standard M.2 NVMe drives. Xbox owners can use the SN850P only as external storage by installing it in a USB enclosure, but this configuration limits you to storing and playing backward-compatible Xbox One games while Xbox Series X|S optimized titles must run from internal storage or official expansion cards. This restriction stems from Microsoft's architectural decisions rather than any limitation of the SN850P itself, but it means PlayStation 5 owners get far more flexibility in their storage expansion options.

PC compatibility extends to any system with an available M.2 slot that supports M-key connections and PCIe connectivity, which encompasses virtually every desktop motherboard manufactured since 2017 and most laptops with user-accessible M.2 slots. The drive works perfectly in both PCIe 4.0 and PCIe 3.0 systems, automatically negotiating the fastest connection speed your motherboard supports, though PCIe 3.0 systems will cap performance at roughly 3,500 MB/s sequential reads due to interface bandwidth limitations. Windows 10 and Windows 11 include native NVMe drivers that recognize the drive without any additional software installation, while Linux kernels 4.4 and newer similarly support the drive out of the box.

BIOS compatibility is universal among systems manufactured within the last five years, with the drive recognized as a bootable device for operating system installation on virtually all UEFI firmware implementations. Older systems using legacy BIOS may require firmware updates or CSM compatibility mode, but these scenarios have become increasingly rare as the industry completed its transition to UEFI standards. The drive's backward compatibility with PCIe Gen 3 ensures it works even in systems predating the Gen 4 standard, making it a safe upgrade choice for users who might eventually transfer the drive between multiple systems over its five-year warranty period.

Strengths & Weaknesses

The WD_BLACK SN850P's greatest strength lies in its official PlayStation licensing and purpose-built design that eliminates compatibility concerns for PS5 owners. While competitors offer similar speeds at lower prices, they require separate heatsink purchases and careful dimensional verification to ensure PS5 compatibility, whereas the SN850P's integrated cooling solution guarantees it works perfectly with Sony's console right out of the box. The five-year warranty and solid endurance ratings of 600 TBW for the one terabyte model provide peace of mind that this drive will outlast the PlayStation 5's lifecycle, and the presence of DRAM cache ensures consistent performance across diverse workloads rather than just synthetic benchmarks.

Performance credentials place the SN850P among the fastest Gen 4 drives available, with sequential read speeds up to 7,300 MB/s that match flagship competitors from Samsung, Crucial, and SK Hynix. The drive handles random workloads effectively thanks to its DRAM buffer, maintaining snappy system responsiveness during multitasking scenarios that would bog down cheaper DRAMless alternatives. Build quality feels premium with the aluminum heatsink construction and PlayStation branding that adds aesthetic appeal for console enthusiasts who appreciate the official Sony approval rather than generic third-party accessories.

However, the SN850P carries a price premium over competing Gen 4 drives that stems primarily from its official PlayStation licensing rather than any performance advantage. The drive costs $10-30 more than alternatives like the Kingston Fury Renegade, Crucial P5 Plus, or even Western Digital's own SN850X when comparing equivalent capacities, and this price gap becomes harder to justify when those competitors achieve identical or superior performance in independent testing. Real-world benchmarks have shown the SN850P sometimes falls short of its rated speeds, particularly in PlayStation 5 installations where system benchmarks report read speeds around 6,300 MB/s instead of the advertised 7,300 MB/s, though this discrepancy rarely impacts actual gaming performance since even the lower speeds exceed Sony's requirements by a comfortable margin.

The permanent heatsink attachment limits flexibility for users who might want to remove the cooling solution to fit specific motherboard configurations or transfer the drive between systems with different thermal management approaches. While most competing drives offer both heatsink and bare drive versions, the SN850P comes exclusively with its integrated PlayStation-branded heatsink, forcing PC builders to work around its fixed dimensions rather than choosing the configuration that best suits their specific hardware. This decision makes sense for Western Digital's target audience of PlayStation 5 owners but reduces the drive's appeal for pure PC gaming builds where alternative form factors might prove more convenient.

Competition from drives like the Samsung 990 Pro remains fierce, with that drive offering slightly better random write performance and broader availability at similar price points. The Crucial P5 Plus undercuts the SN850P by roughly $20 at the one terabyte capacity while delivering comparable real-world gaming performance, and enthusiasts willing to purchase separate heatsinks can save additional money with bare drives like the WD SN850X that use identical controllers and NAND but lack the PlayStation branding. For PS5 owners specifically, these alternatives require more research and assembly work, but PC gamers gain no tangible benefit from the SN850P's official console certification.

Verdict: Should You Buy It?

Buy this if: You own a PlayStation 5 and want the absolute simplest storage expansion experience with guaranteed compatibility and zero compatibility concerns, you value official Sony licensing and prefer the peace of mind that comes from PlayStation-branded accessories, you want a drive that works equally well in both your PS5 and gaming PC without requiring heatsink swaps or modifications, you're upgrading from a SATA SSD or mechanical hard drive in external USB enclosures and want the full performance benefits of internal NVMe storage, or you need capacities beyond two terabytes since the SN850P offers four terabyte and eight terabyte options that work seamlessly with PS5.

Skip this if: You already own a capable Gen 4 NVMe drive and the performance difference would be marginal since competing drives like the SN850X or Samsung 980 Pro deliver essentially identical gaming performance, you're comfortable purchasing a bare Gen 4 drive and separate heatsink to save $20-40 while achieving the same real-world results, you primarily game on PC rather than PlayStation 5 since the official Sony licensing provides no tangible benefit for desktop systems, you're waiting for Gen 5 drive prices to drop and want to skip the Gen 4 generation entirely, or budget constraints make the price premium over competing solutions difficult to justify for what amounts to marketing and branding rather than performance advantages.