Skip to content

I get commissions for purchases made through links in this article.

WD Black SN850 vs WD Black SN850X: The Practical Difference?

    If you ever search for a Prosumer Gen4 NVMe SSD anywhere, you will definitely get to see WD Black SN850. We all know that it is an expensive and powerful NVMe SSD out there. It targets the premium set of users, games, and enthusiasts. It has got a lot of competitors as well.

    In fact, we have done numerous comparisons of SN850 with different SSDs on SSD Sphere. But, today, we have WD’s own product ready for comparison.

    Yes, we are comparing the all-new WD Black SN850X with the already-popular WD Black SN850.

    You should know that the SN850X is coming with a promise of comparatively higher data read/write speed than the SN850. The 1TB variant of SN850X has 7300MB/s and 6300MB/s theoretical read/write speed.

    If you compare it with the SN850’s 1TB variant, the read speed is 300 MB/s, and the write speed is 1000MB/s higher. We are going to test and reveal these things later in this article. So, keep reading until the end.

    SpecificationWD Black SN850WD Black SN850X
    Storage Variants500GB, 1TB, 2TB1TB, 2TB, 4TB
    Theoretical Read Speed (Seq)7000 MB/s7300 MB/s
    Theoretical Write Speed (Seq)5300 MB/s6300 MB/s
    Random Read Speed1,000K IOPS1,200K IOPS
    Random Write Speed1,000K IOPS1,100K IOPS
    Warranty5 Years5 Years
    Heatsink OptionAvailableAvailable
    EncryptionNot AvailableNot Available

    SN850 doesn’t have a 4TB variant but SN850X comes with a 4TB variant. However, it doesn’t have a 500GB variant like the SN850.

    Moreover, SN850X has a 300MB/s higher data read speed and 1000MB/s write speed. The random read/write speed is also supposed to be higher than the SN850. But, all these things will get tested in the real-time benchmark scores. So, let’s proceed further.

    The test bench is equipped with an Intel Core i5 12600K CPU along with a 16GB DDR4 4800MHz RAM kit. The motherboard is MSI Pro Z690-A DDR5. Both the SSDs are 100% empty during the tests and 2TB variants are utilized to run the benchmark tests. Other variants may have different performance results.

    For these tests, I have used the CrystalDiskMark software. CrystalDismMark is another simple-to-use storage benchmark software. It is generally used to run sequential and random system tests using different file sizes. The default sequential read/write test is 1M at Q8T1 and Q1T1. The default random read/write test is 4KB at Q32T1 and Q1T1. You can easily change these test types along with the total test file size.

    CDM Sequential results bar graph sn850 vs sn850x
    CDM Sequential results bar graph sn850 vs sn850x IOPS

    Do not get confused here. In this test, I have used the Game Modes of these SSDs to check the difference in benchmarks. So, there are three modes i.e. Game Mode On, Off, and Auto.

    3DMark Scores Comparison Bar Graph (SN850 vs SN850X)

    AS SSD is another very popular storage benchmarking software. It again runs some random tests to test sequential and random performance. You can set the test size from 1GB to 10GB. It will give you a score that can be helpful to compare the performance of two different SSDs.

    We have used the 1GB Test size here for our benchmarks.

    AS SSD Benchmark Scores Comparison using a bar graph (SN850 vs SN850X)

    Anvils Storage Utilities is our next benchmark software with a pretty simple interface. It runs all the tests automatically and gives you a final score. A higher number means better performance. It runs a wide array of tests including Seq 4MB, 4K, 4K QD4, 4K QD16, 32K, and 128K, in both read and write formats. The test size here in this case is 8GB.

    Anvil's Storage Utilities scores comparison between sn850 and sn850x

    These benchmarks are done with Game Mode turned On and Off for both the SSDs. There isn’t much difference in the results. But, still, you can see that in the graph below.

    PCMark 10 Storage Benchmark Scores Comparison bar graph

    I am using 1920×1080 HD 1080i resolution for this test. The Test size is 1GB and the Codec is 10bit YUV.

    WD Black SN850 1TBWD Black SN850X 1TB

    Obviously, you have got everything by looking at the benchmark results. But, I would like to tell you that both SSDs are competing hard and creating new trends in the SSD market.

    I am really impressed by the sequential and random write speed 850X is offering. But, SN850 is the winner when it comes to the read operations.

    I can recommend both of these to any user who is looking just for performance. For games and enthusiasts, these both are great SSDs to go with.

    ParameterWD Black SN850XWD Black SN850
    TBW1TB: 600 TBW
    2TB: 1,200 TBW
    4TB: 2,400 TBW
    500GB: 300 TBW
    1TB: 600 TBW
    2TB: 1,200 TBW
    Warranty5-Years Limited Warranty5-Years Limited Warranty
    MTBF (Mean Time Between Failure)1.75 Million Hours
    Technical SpecificationWD Black SN850XWD Black SN850
    NAND Flash TypeSandisk’s TLC NANDSandisk’s TLC 3D
    NAND Flash Layers112
    ControllerWD Proprietary ControllerWD Proprietary Controller
    Controller ConfigurationsTri-core/4-ChannelsNot Specified
    Heatsink OptionAvailableAvailable
    EncryptionNot AvailableNot Available
    WebsiteWD Black SN850XWD Black SN850

    By the time I am writing this article, SN850X is surprisingly cheaper than the SN850 and I hope it remains the same. Between these both, I would recommend going for the SN850X because it has better performance. However, as we discussed earlier, the SN850 is good in terms of write operations.

    Both are using the same TLC NAND Flash from Sandisk. But, both lack data encryption as well.

    Overall, the SN850X is capable of providing you with better results. Now, if you are able to get the SN850 at a cheaper price or if you just want to go for it, there is no problem with it as well.

    Let me know what you think about this article in the comments.

    Kingston KC30007000/7000 MB/s
    256-bit Encryption
    Check Price
    Seagate Firecuda 5307300/6900 MB/s
    256-bit Encryption
    Check Price
    Notify of
    1 Comment
    Newest Most Voted
    Inline Feedbacks
    View all comments
    2 months ago