WD Black SN850 vs WD Black SN770 SSD Comparison

The WD Black SN850 or SN770 SSD – Which One Should You Buy?

Should you buy the WD Black SN850 from 2020 or the WD Black SN770 from 2022? Two drives from the same brand, in the same product series and build on the same interface and protocol – yet remarkably different in price, performance and abilities. Remember when choosing a hard drive or SSD was so fantastically simple? Back when practically all drive media was SATA, the differences between one drive or another were thin and it was more about durability and responsiveness than it was about speed and IOPS. However, ever since m.2 NVMe SSDs arrived on the scene (with a protocol that is built on PCIe architecture), the differences between two near-identical SSDs can be somewhat vast. Currently, the highest-performing commercially available tier of NVMe SSD storage arrives in PCIe Gen 4 x4 architecture and that has allowed SSDs to make jumps from a little over 3,000MB/s performance up to an insane 7,000MB/s+. WD was one of the first brands out there to release a commercially available SSD to provide users access to these performance thresholds back in late 2020 with the release of their WD Black SN850 SSD. When it launched, it did so with little or no competition (the Samsung 980 Pro SSD would not arrive for a month or so) and in 18+ months since its original release, despite many, MANY other 7K throughput ready SSDs arriving on the market from their rivals, this early market release has allowed them to spread hugely across the market, as well as allow more flexible pricing at most retailers and be a regular appearance at seasonal sales (Black Friday, Cyber Monday, Prime Day, etc). Fast forward to 2022 and Western Digital has released another entry into this popular series of SSDs, the WD Black SN770, that although is not being presented as a replacement for the SN850, it IS being presented as a more power-efficient and affordable alternative to the 2020 released SSD. So, which one should you buy, which one is better at different tasks and is it better to save/spend your money on either of these WD Black SSDs? Let’s begin the comparison.

The WD Black SN850 or SN770 SSD – Price and What is Included?

The presentation of the WD Black SN850 and WD Black SN770 SSD, despite the 18 months or so difference in their initial release dates, is largely identical. As mentioned, pricing on both of these SSDs is going to be a factor for different reasons. The WD Black SN850 is certainly the more expensive of the two, but is also regularly on sale at different eShops, so you will almost never be expected to commit to the original 2020 RRP of this SSD. The WD Black SN770 on the other hand is designed and produced on the idea of being more affordable/better-value and so arrives (on all of the capacity tiers) a noticeable degree lower in price and looking at Amazon currently, the WD Black SN770 is around 40% lower in price than the WD Black SN850. Even if you find a Sale/Deal on the WD Black SN850 that knocks a few more % off, that is still a huge price difference.

The presentation at retail of each of these SSDs is largely identical, with both the WD Black SN850 and WD Black SN770 arriving in the gamer focus packaging, as well as highlighting their rated benchmarks for Sequential Read/Write performance. It’s a cool design and you can clearly see where the branding design money was spent.

WD Black SN850	WD Black SN770

Opening up the retail kit for each SSD shows a fairly small quantity of contents. The retail kits for both the WD Black SN850 and WD Black SN770 are made up of the SSD itself and first-time setup/warranty information. That is all you get. Now, most m.2 NVMe SSD are always provided either bare chips or with a heatsink and that is about it, but I am surprised that this isn’t any thermal pads or an m.2 screw included. Still, this is hardly unusual. The plastic shell for each is pretty robust and although this is all fairly blah in presentation inside the box, you can at least see that the SSD is moderately well protected.

WD Black SN850	WD Black SN770

It becomes clear that the price difference and value between the WD Black SN850 and WD Black SN770 SSD is much more about what is on the drive in its entirety than any kind of hidden extras. Let’s talk about the design of these SSDs and how they differ.

The WD Black SN850 or SN770 SSD – Design

The first thing I should mention early on in this comparison between the WD Black SN850 and WD Black SN770 is that the SN850 also can be purchased with a first-party heatsink, something the SN770 does not provide. The heatsink equipped version is around 10-15% more expensive than the bare version, but it is quite a premium quality heatsink and fully surrounds the SN850 in a sealed enclosure that dissipates heat considerably well. Both the WD Black SN850 and WD Black SN770 run a little hot at peak use, so if you have the budget for it and were already considering the SN850 anyway, I would certainly pay a pinch more for the heatsink version.

One of the main arguments that supports buying the first-party heatsink with your SSD is that many arrive pre-applied at the factory level, meaning greater precision on the thermal dissipation placement (directly on the controller and other key chips, not just covering everything inefficiently). Additionally, it will be applied in a dust controller environment and (certainly in the case of the WD Black SN850) be installed expertly and in a closed casing. Here is how the WD Black SN850 looks when you remove its proprietary heatsink.

Heading back to the barebones retail purchase of the WD Black SN850 and WD Black SN770 SSD, lining them up side by side shows that they are similar, but the placement of the logo and chips is notable different. A bit part of how these drives differ in price and performance is precisely down the hardware that each is composed of.

WD Black SN850	WD Black SN770

Each SSD is similar in provisional architecture (both PCIe Gen 4, both using NVMe revision 1.4 and both using 3D TLC NAND), however after even a quick look at the accompanying components (as well as the quality of the ones that are similar) immediately highlights how each of the WD Black SN850 and WD Black SN770 are geared differently.

So, the first thing to discuss is that controller. The controller of an SSD is INCREDIBLY important. The build and architecture of any SSD is actually surprisingly similar to a regular PC. The controller is the ‘CPU’, making all the decisions and managing the exchanges of data. In the case of each of the WD Black SN850 and WD Black SN770 SSD, both use an in-house controller (i.e no 3rd party supplier involved) and they are provided by Sandisk (a WD subsidiary). The controller of the WD Black SN850 is arguably the better of the two and despite it being an older controller, still manages to provide higher performance and software options such as encryption that the SN770 does not. The WD Black SN770 SSD controller, although more modern, has to manage another whole area of data processes thanks to the SN770 arriving without DRAM. Why is this important and how does it affect the performance?

WD Black SN850	WD Black SN770

The DRAM on an SSD is comparable to the memory that you would find on a normal PC and is using as a buffer area for the controller to plot, index and coordinate processes on the fly. Memory/RAM is integrated into the smooth running of a system and the WD Black, instead of onboard memory, using a smaller portion of client system hardware memory in order to conduct these buffering processes. This means the WD Black SN770 SSD is lower in price due to the fewer components AND also means it is using less power internally. The WD Black SN850 on the other hand arrives with 1/2GB of DDR4 memory on board. So s this process of the SSD borrowing memory from the host hardware client good to bad?

WD Black SN850	WD Black SN770

In lighter use and less heavily sustained activities, the SSD uses some of the core system available memory (known as HMB, host Memory Buffer) and it allows the drive to use memory that was otherwise being unusual but still powered to do its indexing, tabling and calculations on the fly. That said, the WD Black SN770 only uses a very small amount of memory (much, MUCH less than the onboard quantity of the WD Black SN850 features) and that can become a problem if 1) your client system is already using all/most of the memory on currently software processes (eg graphical processes, which are noticeably hungrier), 2) you are running sustained SSD operations that exceed the available memory/hardware of the controller, which would severely bottleneck the drive immediately, or 3) you are using a less generic hardware architecture (such as a PS5 with its closed architecture) that does not adequately support host memory buffer protocol – this would result in a similar quickly emerging bottleneck.

That is not the only main difference between these SSDs and this bring sus onto NAND. NAND are the chips onboard the SSD where your data actually lives (think of NAND in our ‘PC’ simile as the actual data storage drive media). Now, they are different (in the example of a 1TB SSD) in two key areas. Both use 3D TLC NAND, which is the industry recommended middle ground between performance, durability and price point. However, the WD Black SN850 from late 2020 arrives with 96L NAND and the SN770 arrives with 112L NAND. It is a small difference, but does allow slightly higher performance and durability leveraging. However, this is immediately countered by the WD Black SN850 spreading its 1TB across two 512GB NAND modules, whereas the WD Black SN770 has a single block of 1024GB SanDisk memory. More often than not, the larger the number of NAND modules on an SSD’s PCB board results in higher performance (as it means typically multiple NAND are being read/written from at once when access to the SSD is in progress). The SN770 has clearly opted for this for reasons of efficiency and power use, but also as the SSD has no DRAM, it needs to keep things a little simpler.

WD Black SN850	WD Black SN770

Regardless, the rear of each of the WD Black SN850 and WD Black SN770 1TB SSDs is largely identical, with each drive being a single-sided (SR / 1R) design. Likewise, both SSDs are 2280 in length, so pretty much any hardware environment that can support one physically, will support the other – just don’t forget that HMB is going to be a problem if your hardware does not fully support it.

WD Black SN850	WD Black SN770

And when it comes to systems that are less supportive of host memory buffer, one hugely popular one is the PS5 console and although the WD Black SN850 SSD is one of the most recommended SSDs for upgrading that system (recommended in fact by PS5 designer and engineer Mark Cerney), the WD Black is not compatible with PS5 expansion upgrades (testing to demonstrate this coming soon). The WD Black SN850 still continues to be one of the most popular PS5 SSD upgrades out there and here is a video below from our NASCompares Youtube testing series:

So, now you know how these two SSDs compare in hardware architecture. Let’s dig into how that translates into the performance of the WD Black SN850 and WD Black SN770 SSD. We will first look at the officially reported performance stats and then compare those against the testing we performed on both in-house.

The WD Black SN850 or SN770 SSD – Official Performance Stats

Unsurprisingly, the more expensive WD Black SN850 is the higher-performing SSD when compared with the SN770. This difference in performance also extends vitally towards sustained use and users who are weighing up the pros and cons of each will crucially need to think about the potential performance and workload of their current system. The reported performance and durability below represent maximums and although the highest points of sequential throughput and 4K random IOPS on the SN850 SSD are only achievable of particularly powerful systems, the high points of the SN770 are actually more achievable on mid-range systems.

The big takeaway here is that if the system you intend to install the WD Black SSD into is NOT prosumer grade, then the maximum read/write that you will see in either the WD black SN850 or SN770 is going to be a lot closer than you might think and any additional price, power use and heat that the WD Black SN850 generates might be to little benefit. Additionally, the durability on the WD Black SN770 SSD is largely the same as the SN850, despite its lower performance, so you won’t be seeking out any additional workload out of the more efficient drive. Let’s get the SN770 SSD into the test machine and see how it performs.

The WD Black SN850 or SN770 SSD – Testing

So, for testing the WD Black SN850 and WD Black SN770 SSDs, these tests were run a mid-range PC architecture and featured benchmarks from CrystalDisk Benchmark, ATTO Disk Benchmark, AS SSD and AJA Speed Testing. The details on the tech machine were as follow:

Test Machine:

• Windows 10 Pro Desktop System
• Intel i5 11400 Rocket Lake – 6-Core 2.6/4.4Ghz
• 16GB DDR4 2666MHz Memory
• Intel B560M mATX Motherboard
• OS Storage, Seagate Firecuda 120 SSD
• Test SSD connected to Secondary PCIe Gen 4×4 M.2 Slot

All tests for the separate SSDs were conducted in separate sessions, with a 1-minute cooldown between each (to allow the SSD a reasonable amount fo time to flush the cache and also cool down its components. The full details of the testing and comparing these SSDs is covered in my review of each of these SSDs, but also highlighted in the video below from the NASCompares YouTube channel:

So, let’s go through how each of these 1TB SSDs compared in their benchmarks. I fully anticipate the WD Black SN850 SSD to be the higher performer overall (as you might expect from the hardware architecture and already brand reported figures) but just how much higher will it be and will it justify the higher price point? Let’s take a look.

Temperature During Tests

Before we even get to the results and compare them, it is worth highlighting that in the testing I used the WD Black SN850 SSD with the proprietary SSD heatsink and the WD Black SN770 with a 3rd party generic $10 m.2 heatsink. Both SSDs ran a little hotter than most that I have tested (not unusual, as the bulk of the others use the same Phison E18 or Innogrit IG5236 controller in 2022), but the WD Black SN770 certainly ran hotter. Part of this was the less efficient heatsink (only marginally) but more because of how it is less suitable for sustained usage – which is pretty much what 80-90% of SSD benchmarking is!

WD Black SN850 (1st Party H/S)	WD Black SN770 ($10 H/S)

The first round of performance testing was using CrystalDiskMark Benchmarking with 3 different file scales at 1GB, 4GB and 16GB. Unsurprisingly the WD Black SN850 was ahead by a mile in the Read performance by around 1,800MB/s, however, in write performance, it was much narrower with 300-400MB/s difference. The WD Black SN850 also displayed a similar level of Read/Write difference in terms of random 4K IOPS. All these figures are comparable to those issued by the brand, but I will add that the WD SN770 was using fewer system hardware resources in my PC in order to hit those numbers comparatively.

CrystalDisk Benchmark 1GB Test File

WD Black SN850	WD Black SN770

CrystalDisk Benchmark 4GB Test File

WD Black SN850	WD Black SN770

CrystalDisk Benchmark 16GB Test File

WD Black SN850	WD Black SN770

The next test was with ATTO and once again, from traditional Throughput in Read/Write to the IOPS, I saw a similar BIG difference in read activities, but noticeably smaller in write. If you Are a gamer, you will almost certainly be 95% focused on that read benchmark, however, if you are going to use this as an IS drive and are going to be creating long-running content or streaming for hours at a  time, then this write figure is more important. Regardless, the WD black was still a good distance again on all counts.

ATTO Disk Benchmark 256MB Test File, Sequential Read & Write

WD Black SN850	WD Black SN770

ATTO Disk Benchmark 256MB Test File, I/O Testing

WD Black SN850	WD Black SN770

ATTO Disk Benchmark 1GB Test File, Sequential Read & Write

WD Black SN850	WD Black SN770

ATTO Disk Benchmark 1GB Test File, I/O Testing

WD Black SN850	WD Black SN770

ATTO Disk Benchmark 4GB Test File, Sequential Read & Write

WD Black SN850	WD Black SN770

ATTO Disk Benchmark 4GB Test File, I/O Testing

WD Black SN850	WD Black SN770

The next test was AS SSD in NVMe mode and although it is a little more stringent in its measurements compared with more artificial test scenarios found in CrystalDiskMark, it is still a great tool for mixed SSDs in general. The WD Black SN850 was consistently 1,000-1,500MB/s higher in performance in all tests in read or write traditional throughput, with the larger the file type that was being tested (1GB, 3GB and 5GB here) consistently raising the overall score in favour of the WD Black SN850. Another solid (and arguably quite predictable) win.

AS SSD 1GB Test File, Sequential Read & Write

WD Black SN850	WD Black SN770

AS SSD 3GB Test File, Sequential Read & Write

WD Black SN850	WD Black SN770

AS SSD 5GB Test File, Sequential Read & Write

WD Black SN850	WD Black SN770

Let’s summarize everything and conclude this comparison of the WD Black SN770 and WD Black SN770 below.

The WD Black SN850 or SN770 SSD – Conclusion & Verdict

It was always going to be the WD Black SN850 SSD that won all the performance benchmarks (official or my own) and this comparison was never about deciding if the WD Black SN770 could outperform its bigger and older brother, it was about deciding how much bigger/better it is and whether that can justify the bigger price tag. The WD Black SN770 SSD is a great SSD for more power-efficient systems or those that are not going to be running high-end gaming processes. Likewise, the SN770s steading and consistent write performance in smaller/shorter processes make it still very suitable for content creators that need a scratch disk or want a local drive to edit on that needs a good level of performance, but not one that you are going to be aware of power use over on portable laptop batteries. It IS a good SSD that I wish WD had released much sooner, rather than ONLY releasing a premium SSD for 18 months whilst their rivals in Seagate, Samsung and Sabrent released PCIe 4 SSDs in 7K and 5K versions more than a year ago. Not all buyers have systems that are actually capable of hitting 7,000MB/s or higher and for those buyers, the WD Black SN770 SSD makes sense. However, you cannot ignore the fact that if you are PC/PS5 gamer that needs games storage (as AAA titles are starting to land in the 100s of GBs now), someone working on 4K media in post-production or are running databases of high frequency but low volume databases are ALL going to be significantly better off with the WD Black SN850 in the long run and its hardware justifies the price difference even a year and a half since its original release.

Full Review of the WD Black SN850 and the WD Black SN770 SSD

Wna to learn more about the WD Black SN770 SSD or the WD Black SN850 SSD? I have reviewed and benchmarked both in lots of detail (as well as extensively tested the WD Black SN850 across around 35 games on the PS5 over on YouTube HERE). So if you want to learn more about these SSDs, you can use the links below to the video are written reviews for both of these WD Black SSDs. Thanks for reading!

📧 SUBSCRIBE TO OUR NEWSLETTER 🔔

Δ

🔒 Join Inner Circle

Get an alert every time something gets added to this specific article!

NOTIFY ME

Want to follow specific category? Also Read...Samsung 990 PRO vs WD Black SNSabrent Rocket 4 Plus versus WSeagate Firecuda 530 vs WD BlaWD Black SN850X vs Sabrent RocWD Black SN850X vs Seagate FirWD Black SN850X SSD Review & TWD Black SN850X SSD ReviewWD Black SN850 vs WD Black SN7WD Black SN770 SSD ReviewWD Black SN770 SSD Review - Mi 📧 Subscribe

You can also follow specific search terms:

This description contains links to Amazon. These links will take you to some of the products mentioned in today's content. As an Amazon Associate, I earn from qualifying purchases. Visit the NASCompares Deal Finder to find the best place to buy this device in your region, based on Service, Support and Reputation - Just Search for your NAS Drive in the Box Below

Need Advice on Data Storage from an Expert?

Finally, for free advice about your setup, just leave a message in the comments below here at NASCompares.com and we will get back to you. Need Help? Where possible (and where appropriate) please provide as much information about your requirements, as then I can arrange the best answer and solution to your needs. Do not worry about your e-mail address being required, it will NOT be used in a mailing list and will NOT be used in any way other than to respond to your enquiry.

Your Name (required)

Your Country (required)

Your Email (required)

Subject

Estimated Budget

Storage in GB/TB Required (if NAS, DAS or SAN)

Use case environment (Business/Home)

Your Message (900 char. Or use Fast Track)

By clicking SEND you accept this Privacy Policy
Question will be added on Q&A forum. You will receive an email from us when someone replies to it.
🔒Private Fast Track Message (1-24Hours)

Δ

TRY CHAT Terms and Conditions

If you like this service, please consider supporting us. We use affiliate links on the blog allowing NAScompares information and advice service to be free of charge to you.Anything you purchase on the day you click on our links will generate a small commission which isused to run the website. Here is a link for Amazon and B&H.You can also get me a ☕ Ko-fi or old school Paypal. Thanks!To find out more about how to support this advice service check HEREIf you need to fix or configure a NAS, check Fiver Have you thought about helping others with your knowledge? Find Instructions Here  

 

Or support us by using our affiliate links on Amazon UK and Amazon US

    

 

Alternatively, why not ask me on the ASK NASCompares forum, by clicking the button below. This is a community hub that serves as a place that I can answer your question, chew the fat, share new release information and even get corrections posted. I will always get around to answering ALL queries, but as a one-man operation, I cannot promise speed! So by sharing your query in the ASK NASCompares section below, you can get a better range of solutions and suggestions, alongside my own.

☕ WE LOVE COFFEE ☕