Western Digital WD_BLACK SN850X

The SN850X 4TB hits 7,300 MB/s reads and lands in the 92nd percentile for random performance, making it one of the fastest PCIe 4.0 drives we've tested. Users rate it 92/100 across 1,301 reviews, and the 4TB capacity means you can actually keep your whole library installed. The only real downsides are the 69th percentile endurance rating and the USD 144 price spread between vendors.

Let's talk numbers. The SN850X's 7,300 MB/s read speed is near the ceiling of what PCIe 4.0 can do, and the 6,600 MB/s write speed keeps up nicely. Random performance is where this drive really flexes though. 1,200K random read IOPS and 1,100K random write IOPS put it in the 92nd percentile for random operations in our database. That's the kind of performance that makes Windows boot feel instant and game load screens disappear.

It's got TLC NAND and a DRAM cache, which is the combo you want for sustained performance. The 2,400 TBW endurance rating is solid, though it's only in the 69th percentile, so heavy workstation users who write terabytes daily might want to keep an eye on that. For gamers and general use, you'll likely never hit that limit. The optional heatsink version helps maintain peak speeds during long sessions, and the WD_BLACK Dashboard software adds Game Mode 2.0 and RGB control if you go that route.

Against the Samsung 9100 PRO, the SN850X holds its own on speed while often coming in cheaper, and several reviewers specifically bought it as a Samsung 980/990 alternative after those drives had firmware issues. The Kingston KC3000 is a solid competitor with similar PCIe 4.0 speeds, but the SN850X's random performance and 4TB capacity give it an edge for heavy multitaskers. The Seagate FireCuda 530R is another strong option, though it tends to run pricier for comparable specs. The Crucial T705 is a PCIe 5.0 drive that will beat the SN850X on raw sequential numbers, but you'll pay a premium and need a compatible motherboard to actually see those speeds.

The SN850X 4TB runs anywhere from USD 656 to USD 800 depending on where you shop, and that USD 144 spread is worth paying attention to. Newegg currently has the best deal at the lower end of that range. At USD 656, you're getting top-tier PCIe 4.0 performance and 4TB of storage for a price that undercuts several competitors. Users consistently mention value for money as a strength, especially when it's on sale. At full price near USD 800, it's harder to justify unless you specifically need the capacity and speed combo.

The WD_BLACK SN850X 4TB hits 7,300 MB/s sequential reads and 6,600 MB/s writes, which puts it in the top tier of PCIe 4.0 drives we've tested. That's backed by 1,200K random read IOPS and 1,100K random write IOPS, so it's not just fast in big file transfers, it's snappy when your OS is doing a thousand little things at once. The 4TB capacity is a big deal too, landing in the 93rd percentile for storage space among all drives in our database.

User sentiment sits at 92/100 across 1,301 reviews, and the social proof is even stronger at the 97th percentile. People genuinely like this drive. The main complaints are firmware concerns on early units and the fact that the heatsink version costs extra. But the overall picture is clear: this is one of the best gaming and workstation SSDs you can buy right now, especially if you catch it on sale.

If you're doing heavy workstation workloads that involve writing multiple terabytes per day, the 2,400 TBW endurance rating at the 69th percentile might give you pause. There are drives with higher endurance ratings if you're constantly hammering the drive with writes. Also, if you need a portable drive, look elsewhere. The portable use score of 28.6/100 is a real letdown, and this is clearly designed as an internal drive. And if you're on a tight budget, the USD 656 to USD 800 price range might push you toward a smaller capacity or a more budget-focused drive.

The WD_BLACK SN850X 4TB is one of the best PCIe 4.0 drives on the market right now. The 7,300 MB/s read speed, 92nd percentile random performance, and 4TB capacity make it a no-brainer for gamers and power users who want to stop deleting games to make room. The 92/100 user sentiment score backs up the spec sheet, and the only real caveats are the middling endurance rating and the fact that you should update the firmware when you get it. If you can grab it near USD 656, do it.