We purchased the Corsair EX400U 4TB because we wanted to see how it performs compared to many of the USB 3.2 Gen2 and 2×2 drives that we have reviewed previously. With USB4, we are promised read speeds at up to 4GB/s and write at 3.6GB/s, making this faster than many early NVMe SSDs, despite it being a small USB drive. With that, let us get to the review and what we found.

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Corsair EX400U 4TB USB4 Portable SSD Hardware Overview
The device itself is a small gunmetal chassis with a Corsair logo on top.

On one side we have a USB Type-C port for our USB4 connection.

The rest of the drive does not have a lot.

Here is another angle.

On the bottom, we get a label with information, although we wish it had 4TB written larger. When you have many of these, it makes life much easier if you can see the capacities in large print.

That circle may not seem significant at first, but then we realized that it is actually a magnetic attachment. So if you have a newer iPhone, for example, you can use this drive to capture 4K ProRes video directly to the SSD, and just affix the SSD via the MagSafe magnets on the back of the phone, then a short USB4 cable between the phone and device. That is a nice feature if you shoot a lot of high-end video, and one we have not seen on lower-end SSDs.
The package comes with a short USB4 cable, but not much else.

Here are the performance specs which are pretty good. It will be interesting to see if we can hit those specs.

Next, let us get to the performance so we can see what this drive offers.




Nice! Thank you.
Did you ever open-it-up?
>we are promised read speeds at up to 4GB/s and write at 3.6TB/s
typo, should be GB/s for write