WD_BLACK SN850X 8TB SSD Review - The New King of High Capacity

TweakTown Rating: 95%

Our Verdict

It's by far the highest performing 8TB retail SSD we've encountered to date. It's the New King of High Capacity.

Pros

• Capacity
• User experience performance
• Pricing

Cons

• None

Should you buy it?

AvoidConsiderShortlistBuy

Buy at Newegg for $1287.37 USD

Lowest price in 30 days

Also at Amazon $1499 USD

Buy at Newegg for $2653.78 CAD

Up 33.4% vs 30 days ago

Also at Amazon

Buy at Amazon for £1015

View price at Amazon

Also at PC Case Gear

Introduction & Drive Details

Well, we finally have another 8TB M.2 NVMe SSD to compete with the Phison E18 8TB that is currently being sold by various SSD merchants. The most famous of the Phison 8TB SSDs is undoubtedly Sabrent's Rocket 4 Plus 8TB, which we first reviewed over two years ago.

This is certainly a welcome addition to the current crop of high-capacity retail NVMe SSDs. So now we have 2- players in the ultra-capacity game - Phison and WD. Phison E18 controlled SSDs are getting a bit long in the tooth and really struggle to keep up with more modern SSDs as even most current 4-channel DRAMless SSD deliver a better overall user experience.

The same could be said of the WD_BLACK SN850X in that it is also a 2-year entity and can be outperformed by some of the better 4-channel DRAMless SSDs out there. However, from the get-go, the WD_BLACK SN850X ran circles around the best-performing E18-controlled SSDs. This trend continues today, as you will see, especially at the 8TB capacity point where the Phison-made offering is notably weak on the real-world performance front.

The 8TB SN850X, like the rest of the capacity points in the series, is powered by an 8-channel Sandisk controller. No change there at 8TB. However, when we get to its flash array, we find that WD has swapped out the BiCS5 that arrays the smaller capacity points, with some newer and better BiCS 6 flash. Arrayed on the 8TB model are four 2TB packages composed of 1024Gbit BiCS6 dies stacked 16-high.

So that means the 8TB should be the fastest of the series? Actually no, because 512Gbit BiCS 5 flash is still slightly faster than 1024Gbit BiCS 6 - at least it is when it's behind the same Sandisk controller that has always powered the SN850X series. This is why the 8TB SN850X is spec'd slightly lower than the 2TB and 4TB models.

The WD_BLACK SN850X 8TB has more going for it vs. the Phison-made 8TB than just significantly better performance, it's significantly cheaper as well. With an MSRP of $849.99, it is up to several hundred dollars cheaper than its Phison competition at 8TB.

Best Deals: WD Black SN850X 8TB NVMe PCIe Gen4 x4 M.2 SSD

Prices last scanned 3 hours and 47 minutes ago

Today 7 days ago 30 days ago Buy

$1287.37 USD

7 days ago: $1328 USD30 days ago: $1425.45 USD

$1328 USD

$1425.45 USD

BuyBuy at Newegg

$1499 USD

7 days ago: $1299.99 USD30 days ago: $1299.99 USD

$1299.99 USD

$1299.99 USD

BuyBuy at Amazon

$2653.78 CAD

7 days ago: $2999.99 CAD30 days ago: $1989.45 CAD

$2999.99 CAD

$1989.45 CAD

BuyBuy at Newegg

£1015

7 days ago: £998.80

£998.80

-

BuyBuy at Amazon

Check Price

-

-

CheckCheck Price at Amazon

Check Price

-

-

CheckCheck Price at Amazon

Check Price

-

-

CheckCheck Price at PC Case Gear

One final note before we get into the review is that a version with a heatsink that is ideally suited for use with PlayStation 5 is also available for $899.99.

45

Drive Details

45

45

As it is with most Western Digital Storage products, WD offers its excellent toolbox software - Western Digital Dashboard, along with Acronis for Western Digital cloning software - free with its SN850X SSDs Click HERE to get both.

Jon's Test System Specifications

Intel Test System

• Motherboard: GIGABYTE AORUS Z790 Xtreme X
• CPU: Intel Core i9-14900KS - Buy from Amazon
• Cooler: Alphacool Eissturm Hurricane Copper 45 - Buy from Amazon
• RAM: Patriot Viper Xtreme 5 8000 48GB - Buy from Amazon
• Graphics Card: MSI SUPRIM X RTX 3080 12GB - Buy from Amazon
• Case: PrimoChill's Praxis Wetbench - Buy from Amazon
• Power Supply: be quiet! Dark Power Pro 12 1200W - Buy from Amazon
• OS: Microsoft Windows 11 Pro - Buy from Amazon

AMD Test System

• Motherboard: GIGABYTE X670E AORUS Master
• CPU: AMD Ryzen 9 7950X - Buy from Amazon
• Cooler: Alphacool Eissturm Hurricane Copper 45 - Buy from Amazon
• RAM: Sabrent Rocket DDR5 32GB - Buy from Amazon
• Graphics Card: MSI SUPRIM X RTX 3080 12GB - Buy from Amazon
• Case: PrimoChill's Praxis Wetbench - Buy from Amazon
• Power Supply: be quiet! Dark Power Pro 12 1200W - Buy from Amazon
• OS: Microsoft Windows 11 Pro - Buy from Amazon

Because we at TweakTown like to be first at everything whenever we can, we will present our storage performance results for the test subject on both 14th Gen Intel and 7000 Series AMD platforms going forward for the foreseeable future. Because Intel still delivers the best real-world storage performance, (Look Here), our running chart will continue to be Intel-based until AMD can deliver better real-world storage performance than its rival.

Sony PlayStation 5 - M.2 Storage Expansion

PS5 Read Performance

With Sony's wildly popular PlayStation 5 console now enabled for M.2 NVMe SSDs to be used as fast storage expansion, we are including results for PS5 compatible SSDs we test as a part of our reviews going forward.

45

45

For SSDs that don't have an adequately sized PS5 compatible heatsink or other SSDs where the heatsink provided doesn't fit right and can be removed, we both use and recommend Sabrent's unparalleled PS5 heatsink available HERE.

45

45

We only chart SSDs that can deliver a minimum of 5,500 MB/s read, which is Sony's original recommendation.

45

A result here of 6,556 MB/s is the third best result of all-time. Impressive, and at least here anyway, the 8TB model has the upper hand on its lower capacity siblings.

Synthetic Benchmarks: CDM, Anvil, ATTO

CrystalDiskMark

45

45

45

45

45

We employ CDM as our standard measurement for both sequential throughput and Q1T1 random read. In terms of sequential throughput, we find our test subject fully capable of exceeding quoted up to factory throughput specifications. Overall, it's keeping up with its older siblings in terms of sequential throughput but ever so slightly slower at Q1T1 random reads.

Anvil's Storage Utilities

45

45

45

Scoring here is where we begin to see that the 8TB model is less performant overall than the 2TB and 4TB models.

45

45

45

We employ Anvil's random read test as our standard for measuring max random read IOPS. This test is very accurate as it at its core is Iometer skinned over. We test at QD128. The drive is spec's for up to 1,200K IOPS here and we are getting 1,140K IOPS. Good enough considering our more demanding user state. Performance as advertised, and here it is especially impressive.

ATTO

45

45

45

45

ATTO gives us a clear picture of what transfer sizes a particular SSD favors in terms of QD4 sequential throughput. We chart 128K transfers. At a queue depth of four, WD_BLACK SN850X 8TB favors sequential transfers of 512KB or larger when serving data to the host (reading) and 128KB or larger when programming (writing) data.

Real-World Testing: Transfers, 3DMark SSD Gaming Test, PCM10 Storage

Transfer Rates

45

45

45

Our 100GB data transfer test is not your ordinary 100GB of data. Ours is a crushing mix composed of more than 62K files. Write performance, random or sequential, is an infrequent operation, and as such, we do not consider it to be an important performance metric in the consumer space. An example being how many times is a game installed vs. how many times it's played. A transfer rate of 1,916 MB/s is the second-highest write transfer rate we've seen from any flash-based PCIe Gen4 SSD. This is not unexpected as BiCS 6 should be faster here than BiCS 5.

45

45

45

Unlike programming (writing) data, serving data to the host (reading) is typically an important performance metric as it relates to the consumer space. Another top of the PCIe Gen4 food chain performance. Nice.

3DMark SSD Gaming Test

UL's newest 3DMark SSD Gaming Test is the most comprehensive SSD gaming test ever devised. We consider it superior to testing against games themselves because, as a trace, it is much more consistent than variations that will occur between runs on the actual game itself. This test is the same as running the actual game, just without the inconsistencies inherent to application testing. In short, we believe that this is the world's best way to test an SSDs gaming prowess and accurately compare it against competing SSDs. The 3DMark SSD Gaming Test measures and scores the following:

• Loading Battlefield V from launch to the main menu.
• Loading Call of Duty Black Ops 4 from launch to the main menu.
• Loading Overwatch from launch to the main menu.
• Recording a 1080p gameplay video at 60 FPS with OBS (Open Broadcaster Software) while playing Overwatch.
• Installing The Outer Worlds from the Epic Games Launcher.
• Saving game progress in The Outer Worlds.
• Copying the Steam folder for Counter-Strike Global Offensive from an external SSD to the system drive.

45

45

45

Gaming is a performance metric that matters to most DIY consumers, especially for the enthusiast crowd that TweakTown caters to. Now we've reached the point where results start to matter as they are a direct reflection of user experience.

Pretty decent score here, roughly 10% lower than the 2TB and 4TB models, but massively better than the other 8TB SSD appearing on this chart. This is, in large part, why we are crowning the WD_BLACK SN850X 8TB as the new high-capacity king.

PCM10 Storage Tests

PCMark 10 Storage Test is the most advanced and most accurate real-world consumer storage test ever made. There are four different tests you can choose from; we run two of them. The Full System Drive Benchmark and the Quick System Drive Benchmark. The Full System Drive Benchmark writes 204 GB of data over the duration of the test. These tests directly correlate with mainstream user experience.

PCMark 10 Full System Drive Benchmark

This test writes 204GB data and covers a broad range of common consumer tasks, including booting Windows 10, file transfers, Adobe and Office applications, and startup times for games including Battlefield V, COD Black Ops 4, and Overwatch. Unlike synthetic numbers, this is comprehensive real-world data which is why we use it to rank SSDs in terms of user experience.

45

45

45

Again, it's good, but not as good as the 2TB and 4TB models when it comes to real-world performance. In terms of performance at the 8TB capacity point, our test subject is at a whole other level when compared to the Phison-made 8TB SSD.

PCMark 10 Quick System Drive Benchmark

The Quick System Drive Benchmark writes 23 GB of data over the duration of the test.

45

45

45

Of all the benchmarks we run, it can be argued that this one offers the best reflection of a typical consumer use case scenario. Again, slightly behind its lower capacity siblings, but total domination for its capacity point.

Final Thoughts

The 8TB capacity point is indeed the rarest of the rare when it comes to consumer NVMe SSDs. To this point, there have been only two of them. Of those two, the WD_BLACK SN850X 8TB is vastly superior as it relates to user experience, or performance that matters. Additionally, with an opening price point of just $849.99, it's obvious who the winner here is.

45

We rank SSDs in terms of overall user experience (performance where it matters most) as expressed by PCMark 10 storage and 3DMark gaming storage tests. Currently, we consider a user experience score of 15K or more to verify an SSD as a TweakTown Elite performer.

45

It's the best of its kind that we've ever encountered and as such is worthy of our highest award. Editor's Choice.