SanDisk X400 SSD Review (512GB)


For today’s analysis, we were not given a fresh drive to work with as we usually do. Our results are of that of a drive that has been through heavy testing beforehand by SanDisk themselves. Over the course of our benchmarking, the SanDisk X400 did very well however, especially considering the multiple TBs of wear it already had. It was able to pull off sequential speeds of 556MB/s read and 536MB/s write in ATTO. 4K speeds were great in Crystal Disk Mark, reaching 42MB/s read and over 150MB/s write. And, in AS SSD it achieved near spec read and write IOPS performance of 95K/75K.

It also did very well in our PCMark suites. First, it reached an average score of 73K in Vantage and most speeds averaged in the 300-400MB/s range. Then, in PCMark 8 the X400’s bandwidth performance was average that of the rest of the comparison pool, but it was able to rival that of the Samsung 850 EVO in terms of latency results, our top performing TLC drive.

SanDisk X400 SSD Angle

Next, during our real-world transfer and power testing, it put out some very respectable results. While it wasn’t the fastest TLC drive to transfer our 30GB of movies, it was above average. Following that, we were able to see that it also consumed less power during the task than all the other drives in our comparison. Even its idle and max power consumption results were some of the best yet, making it a very efficient SSD.


The SanDisk X400 family of SSDs are their top-tier client SSDs. Utilizing Marvell’s 4-channel 88SS1074 controller and their latest 15nm TLC NAND, the X400 family delivers a great mix of performance and value. It is available in a wide variety of capacities up to 1TB, of which both 2.5″ 7mm and single-sided M.2 2280 form factors are attainable. Features such as nCache 2.0, DataGuard, LDPC, and AES 256-bit and TCG Opal 2.0 support, also help to differentiate it from the crowd.

SanDisk X400 SSD

All this ties together to make the X400 the perfect device to migrate to from a slow hard drive in a business environment. It has almost everything you are looking for, whether it is high reliability, great performance, an awesome feature set, or just great price at around $0.24-$0.31/GB. With a 5-year warranty and great endurance numbers on top, the X400 is quite hard to beat. Therefore, we are giving it our Top Value Award! If you are looking to update your infrastructure to the latest in flash, be sure to…

Check out the SanDisk X400 at Amazon Today!


SanDisk X400 Report

Build and Components
Price and Availability

Top Value

Packed with TLC NAND, one may reserve suspicions as to how well the top-tier SanDisk X400 will actually perform, however, based on our results, it does not disappoint. With an awesome feature set, good performance, a 5-year warranty and up to 1TB capacity in a single sided M.2 2280 form factor, the SanDisk X400 is a great value.

User Rating: 2.82 ( 16 votes)


  1. blank

    Hey Sean-Is this a replacement for the Ultra 2??????
    Would have liked to have seen how large the SLC cache is-guessing around 8GB.

    If you ever get a chance-could you test a Samsung 650.It’s a strange one,it sits
    below the 750 EVO (which is not much more than a 640 EVO) and yet best I can
    tell it’s 3d nand.Perhaps lower binned nand that don’t make 850 spec…………….

    • blank

      No, it is not the Ultra II replacement. The Ultra II is part of their consumer product line. The X400 is part of their client/business product line.

      We will look into the Samsung 650.

  2. blank

    Hi Sean (or anyone:) ), I was about to buy a 512GB X400, but noticed that at, the older X300 series seems to have outperformed the X400 in write speeds by as much as 50%. Can anyone provide any insight?

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