WD Black SN850X 2023 review - sleek, swift and simple

a close-up shot of a Western Digital WD Black SN850X SSD resting on top of an Elder Scrolls background

a close-up shot of a Western Digital WD Black SN850X SSD resting on top of an Elder Scrolls background

The flagship SSD from Western Digital just got even better. An updated version of the 2021 beast, the WD Black SN850X is a sleek and powerful SSD that offers lightning-fast transfer speeds at a reasonable price.

Essentially the RTX Super variant of Western Digital’s high-end storage, the ‘X’ that garnishes the updated SN850’s name is more than just marketing fluff. It’s not an entirely overhauled design, but it’s a marked upgrade over its predecessor that anyone looking for a new SSD should be more than comfortable with.

Available in several storage configurations, you can find the SN850X in 1TB, 2TB, or 4TB variants. You can also purchase these with or without an additional heatsink to keep the storage device cool during heavier transfers. However, even over a 24-hour period of constant downloads, transfers, and rendering to the drive, the SN850X didn’t have any temperature issues on our device without the additional heatsink.

A WD Black SN850X SSD resting against a Skyrim box.
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Pay no attention to the out-of-focus nature of this picture; my camera lens is just fine, thank you.

As a PCIe Gen 4 device, the SN850X hits the absolute limit of its available transfer speeds. Until Western Digital releases a Gen 5 SSD — the long-awaited SN950N, we presume — this is the best of the best, with blazing fast transfer speeds of 7,300MB/s sequential read and 6,600MB/s sequential write. If you opt for the base 1TB model, that write speed is slightly lower at 6,300MB/s, although at that point the speed difference is negligible.

The 1TB model SN850X does also fall behind substantially in random read speed compared to its bulkier brothers. In our testing, we were fortunate enough to get hold of the 2TB model, the sweet spot of storage options, which has a random read of 1,200K IOPS, the same as the larger 4TB model. In comparison, the 1TB drive has a random read of almost half that at 800K, although its random write is identical at 1,100K.

Outside of PC use, Western Digital’s speedy SSDs are touted as perfect additions to the PlayStation 5 console. Whether you have a Digital Edition or standard model, you’ll be able to upgrade storage with WD’s new drive. However, you will have to fork out extra for the additional heatsink for optimal PS5 performance.

For the SN850X, WD has touted its new Game Mode 2.0 software as an important addition, but it seems more like a marketing gimmick. Alongside its integration with the brand’s dashboard app to monitor drive health and change numerous settings, Game Mode is designed to make video game loading and asset streaming easier, and it automatically turns on when it detects a game running.

Using predictive loading algorithms, Game Mode 2.0 does offer a slight boost in video game loading, and even on games with asset pop-in issues — such as The Last of Us Part 1 and Star Wars Jedi: Survivor — we noticed marginal improvements on asset streaming, but not enough to really write home about. Nevertheless, it’s an improvement, and it’s noticeable if you squint.

A WD_Black SN850X with a heatsink being held by a random hand
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If you want to use the WD_Black SN850X in a PS5, you'll need to get the model with a heatsink attached.

Game Mode 2.0 may well be a game-changer for some titles out there that suffer from streaming bottlenecks, say, Star Citizen, perhaps. However, it’s not the be-all-end-all that SN850X marketing claims it is. At the end of the day, it’s DirectStorage API compatible anyways, and that’s all that really matters on a Windows PC.

In more technical jargon, the WD Black SN850X has one more major upgrade over its predecessor. Instead of BiCS4 flash, WD has upgraded to BiCS5, which is how the manufacturer has shrunk its 4TB SKU into just a slim single-sided device. It’s an impressive feat, and is becoming the norm for higher-capacity SSDs. Hopefully, the next-gen PCIe Gen 5 drives will be able to push single-side storage even higher in the future.

At an RRP of £96.99 for 1TB, £153.99 for 2TB and £314.99 for 4TB, the WD Black SN850X is a strong competitor in the SSD market. With just a £20 additional fee for the attached heatsink with RGB, it’s a strong option for gamers and video producers alike.

WD SN850X Black
The Western Digital SN850X Black is a blazing-fast Gen-4 SSD with a sleek single-stack profile. If you're in need of more storage, this is the slab for you.
Western Digital
SSD
WD Black
9 out of 10