Western Digital Black SN850X

The WD Black SN850X is a top-tier PCIe 4.0 NVMe drive with 7,300 MB/s read speeds and excellent random performance. It's a direct competitor to the Samsung 990 Pro, often at a lower price, and avoids Samsung's recent firmware drama. Prices range from $185 to $277 in the US, so shop around for the best deal. If you want near-max Gen4 performance without paying PCIe 5.0 prices, this is one of the best options available.

The headline numbers are 7,300 MB/s sequential read and 6,300 MB/s sequential write. In real terms, that means a 100GB game install copies in roughly 15-20 seconds if the source drive can keep up. But sequential speeds are only part of the story. The random performance is where this drive really shines. 800K random read IOPS and 1.1 million random write IOPS put it in the 89th percentile overall, which translates to snappy boot times, fast app launches, and smooth multitasking when you've got a dozen browser tabs and a game running at once.

Those random numbers matter more than the sequential ones for everyday use. Loading a game level or opening a project file involves thousands of small reads scattered across the drive, not one giant file transfer. The SN850X handles that workload better than most Gen4 drives out there. The DRAM cache helps too, keeping the drive responsive under mixed workloads. Endurance sits at 600 TBW, which is solid but not exceptional, landing in the 69th percentile. For most people that's years of heavy use, but if you're constantly rewriting large video files, you might want to keep an eye on it.

The Samsung 990 Pro is the obvious rival here. It's got a slightly higher sequential write speed and a marginally better endurance rating, but it also had that firmware fiasco that scared a lot of buyers away. Several of our customer reviews specifically mention switching to the SN850X to avoid Samsung's firmware issues. The 990 Pro is a great drive when it works, but the SN850X offers nearly identical performance with fewer headaches and often a lower price.

The Kingston KC3000 is another strong Gen4 option. It trades blows with the SN850X on sequential speeds but tends to fall behind on random performance. The Crucial T700 is a PCIe 5.0 drive, so it's faster on paper, but you need a compatible motherboard and it runs hot, which means you're paying a premium for performance most people won't notice. The Team Group MP44 is a budget alternative that undercuts the SN850X on price but gives up meaningful performance, especially on sustained writes. For most buyers, the SN850X sits in the sweet spot: near-top performance without the bleeding-edge price or thermal headaches.

Pricing on the SN850X 1TB is all over the place depending on where you shop. In the US, we're seeing listings from $185 to $277, which is a $92 spread. That's a big enough gap that you really should shop around before pulling the trigger. The lowest US price we found makes this drive an absolute steal for the performance you're getting. In Canada, the spread is CAD 90, ranging from CAD 320 to CAD 410. Again, the cheapest listing is the one to hunt for.

When you compare the SN850X to the Samsung 990 Pro, which is its most direct competitor, the WD drive often comes in a bit cheaper while delivering nearly identical real-world performance. The 990 Pro has a slight edge in some synthetic benchmarks, but you'd be hard pressed to notice the difference in daily use. If you can find the SN850X at the low end of that price range, it's one of the best performance-per-dollar Gen4 drives on the market right now.

The WD Black SN850X is one of those drives that just gets out of the way and lets you do your thing. It's a PCIe 4.0 NVMe drive aimed squarely at gamers and workstation users who want top-tier speed without paying PCIe 5.0 prices. The 1TB model we're looking at hits 7,300 MB/s read and 6,300 MB/s write, which puts it right at the ceiling of what Gen4 can do. You also get TLC NAND, a DRAM cache, and a 600 TBW endurance rating, so it's built to last a while.

Who's this for? If you're building a gaming PC and want load times that feel instant, or you're editing large files and hate staring at progress bars, this drive makes a lot of sense. It's also PS5 compatible, which is a nice bonus if you're expanding console storage. The optional heatsink version is worth considering if your motherboard doesn't have its own M.2 cooling, especially for sustained writes.

What makes the SN850X interesting is the balance. It's not the absolute fastest Gen4 drive in every metric, but it's consistently near the top across the board. Random performance lands in the 89th percentile, features in the 87th, and social proof is basically off the charts at 96th. People buy this drive, they like it, and they tell other people. That kind of track record matters when you're trusting your data to a piece of silicon.

If you're looking for a portable external drive, this isn't it. The SN850X scores a dismal 24.3 out of 100 for portable use, which makes sense since it's an internal M.2 drive. You'd need an external enclosure, and even then, you're not getting the full speed unless you have a Thunderbolt or USB4 enclosure, which adds significant cost. For portable storage, look at a purpose-built external SSD instead.

If you're on a tight budget and don't need bleeding-edge speed, the Team Group MP44 or other budget Gen4 drives will save you money while still delivering solid performance. The SN850X is a premium drive, and if you're just browsing the web and using Office apps, you won't notice the difference between this and a drive that costs half as much. Also, if you have a PCIe 5.0 motherboard and want maximum future-proofing, the Crucial T700 is faster on paper, though you'll pay a premium and deal with more heat.

If you're building a gaming PC or upgrading an existing one, the SN850X is an easy recommendation. The 1TB model gives you enough room for a solid game library, and the load time improvements over SATA or older NVMe drives are immediately noticeable. Pair it with a motherboard heatsink or grab the version with the built-in heatsink if you're doing heavy sustained writes. The PS5 compatibility is a nice bonus if you want to expand console storage later.

For workstation users doing video editing, 3D rendering, or large dataset work, the SN850X holds up well. The strong random performance means scrubbing through timelines and loading project assets feels responsive. The 600 TBW endurance rating is adequate for most professional workloads, though if you're writing terabytes of data daily, you might want to look at drives with higher endurance ratings or step up to a larger capacity model, which typically comes with a proportionally higher TBW.