Corsair EX400U review: Ultra-fast, portable USB-C storage!

Are you searching for an external SSD that provides ultra-fast USB 4 connectivity? Do you need a portable storage solution that is compatible with multiple systems, including Windows, macOS, and iOS? Would you like a portable SSD that connects to your devices via USB-C? If so, you should consider the Corsair EX400U. This compact SSD has some exciting features, including MagSafe compatibility, which will appeal to many Apple users. Read this review to find out how it performs and whether it’s the right choice for your devices:

Corsair EX400U: Who is it good for?

This solid-state drive is an excellent choice for:

• People looking for a portable storage device
• Content creators who need fast external storage
• People with Macs, iPhone and iPads that have USB-C ports

Pros and cons

Here’s what I like about the Corsair EX400U:

• Excellent read and write speeds
• It’s super portable (small and lightweight)
• It has a MagSafe-compatible shell
• Reasonable pricing
• Works great with Windows, Mac, iPhones, and iPads

As for downsides:

• Limited compatibility with Android devices
• It gets hotter than other drives when writing a lot of data

Verdict

Corsair EX400U is a fantastic choice for those seeking portable storage that integrates seamlessly with Apple’s ecosystem of devices as well as Windows. The EX400U offers a solid balance between price and performance, although it isn’t a budget option. Its actual USB 4.0 speeds align with the official specifications, and its magnetic ring allows easy attachment to various devices, working particularly well with MagSafe. Overall, it’s a remarkable product that will satisfy its users.

Unboxing the Corsair EX400U

Corsair EX400U is a portable SSD that comes in a small cardboard box painted in black and yellow. On top of the box, you see a picture of the device, the model name, and its key characteristics.

Corsair EX400U comes in a black/yellow cardboard box

Inside the box is the SSD drive, a short braided USB-C cable, and a leaflet containing safety and compliance information.

This is everything you’ll find inside the box

The unboxing experience for Corsair EX400U is very fast, as you get only the essentials required for using this portable drive.

Design and hardware specifications

Corsair EX400U is a USB4 square portable drive with rounded corners. It’s available only in gray, it measures 6.5 x 6.5 cm or 2.56 x 2.56 inches and weighs just 50 grams or 1.76 oz (without the cable). This is the smallest and lightest portable drive I have ever tested. The top cover features the Corsair company logo, while the back includes a USB-C port and an LED indicator that signals the drive’s functioning status.

Corsair EX400U has a USB-C port on the back

The USB-C cable provided by Corsair is only 30cm long, allowing for data transfers at speeds up to 40 Gbps and 60 Watt power delivery. The Corsair EX400U weighs 92 grams or 3.25 oz with the cable attached.

The included cable is only 30 cm long

According to Corsair, the EX400U offers a maximum sequential read speed of 4000 MB/second and up to 3500 MB/s for the sequential write speed, which is almost double the speed you get from a USB 3.2 SSD drive like the Samsung T9 that we reviewed some time ago. On the bottom of the EX400U, you find a magnetic white circle. It allows you to stick the drive to various metal surfaces and is also MagSafe compatible. As a result, you can easily stick this portable drive to the back of your iPhone 16 Pro Max, connect it through the USB-C port, and transfer your 4K high-resolution videos to it.

On the bottom of the Corsair EX400U, you find a magnetic white circle

The Corsair EX400U portable SSD is available in capacities of 1TB, 2TB, and 4TB, all of which offer the same read and write speeds. It can be safely stored in temperatures ranging from -40°C to 85°C (-40°F to 185°F), and it can be used in temperatures from 0°C to 70°C (32°F to 158°F).

Regarding the operating systems it can work with, the list includes Windows 10, Windows 11, macOS 13, iOS 13, and iPadOS 13 or later. Unfortunately, there’s no Android support. For more technical specs and features, visit this official Corsair EX400U product page.

Spec-wise, the Corsair EX400U is a very fast portable drive, which should provide an excellent experience for Windows, Mac, iPhone, and iPad users.

Using the Corsair EX400U

I connected the Corsair EX400U to my desktop PC, Android devices, and the ASUS Zenbook S 16, which I’ve used as my work laptop for several months. Unfortunately, the EX400U did not work with my Samsung Galaxy S23, but it did function properly with my Xiaomi Pad 6 tablet. I also connected it to a Google Pixel 8 smartphone. While the device successfully detected the Corsair EX400U, I encountered some errors while navigating its file system. Since Android is not listed among the officially supported platforms, I recommend choosing a different portable SSD if you need to use it with Android devices. Windows 11 on the other hand, had no trouble detecting the EX400U and recognized it as a portable NVMe SSD drive. The 1TB model I received for testing was identified as having 932 GB of usable storage capacity.

Corsair EX400U is immediately detected by Windows 11

While there’s no software found on the Corsair EX400U, the drive is compatible with the Corsair SSD Toolbox, which you can use to check the health status of the drive, get firmware updates, clone the content of the drive, wipe it securely, etc.

Corsair EX400U works with Corsair SSD Toolbox

Luckily, you don’t need to use this app to write and read data from the Corsair EX400U. The drive is super fast, and this was immediately evident when I copied the ISO file for the Windows 11 setup from my laptop to the EX400U. The average speed achieved was around 1.81 GB/second. This meant the 5.41 GB file I moved got copied to the SSD in just three seconds.

I copied the Windows 11 Setup in just three seconds

Copying the same file back from the SSD to the laptop was done with a maximum speed of 1.98 GB/second. These are superb speeds.

Copying data from the Corsair EX400U is incredibly fast

The only downside I noticed was that when I was writing a large amount of data to the Corsair EX400U, the drive became slightly warmer than other similar devices I’ve tested. After ten minutes of continuous data writing and reading benchmarks, the exterior temperature of the drive rose to 39.3 degrees Celsius (102.74 degrees Fahrenheit), with the hottest point being in the center. Considering how fast and compact this USB 4 drive is, I don’t find this surprising.

The temperature reached by Corsair EX400U

While the speed of the Corsair EX400U was something that I constantly appreciated during my testing, another feature I liked a lot was the magnetic ring on the back of this drive. It allowed me to attach the EX400U to my laptop, my desktop PC, and MagSafe accessories. This makes it easy to carry the drive around, and its small size and light weight allow you to continue using the device you attach it to.

Corsair EX400U can be attached to metallic surfaces

I very much enjoyed using the Corsair EX400U. This drive was easy to carry and fast. But to see exactly how fast it is, let’s run some benchmarks. Continue reading to see if Corsair’s claims match the actual benchmark results.

Performance in benchmarks

If you have read our past reviews on Digital Citizen, you know that we always run some benchmarks when testing gadgets of all kinds, including portable SSD drives.

To provide a clear comparison of how well the Corsair EX400U performs, I compared it to other portable drives we’ve reviewed in the past: the Samsung T9 and Kingston XS2000. All three drives have a capacity of 1 TB, but while the Corsair EX400U uses USB 4, the others utilize USB 3.2. As a result, I anticipate significant speed differences in favor of the Corsair EX400U.

First, I ran CrystalDiskMark to measure sequential and random read/write performance. Corsair EX400U delivered sequential read speeds of 4058 MB/s and impressive random read speeds. This drive was twice as fast as the SSDs in my comparison. An excellent start! 🙂

CrystalDiskMark – data reading

The Corsair EX400U delivered an impressive 3587 MB/s in sequential write speeds and did very well in the random writing tests, too.

CrystalDiskMark – data writing

Next, I ran the Data Drive Benchmark from PCMark 10 to evaluate the SSD’s performance as a data storage device. As you can see below, the Corsair EX400U had an impressive score of 1781 points, which is 64% higher than the Samsung T9.

The score in PCMark 10

As the final benchmark, I used BlackMagic’s Disk Speed Test. This tool is designed for video professionals who work with large files and need fast storage performance. The results showed that the Corsair EX400U can achieve sequential read and write speeds of about 3005 MB/s and 2661 MB/s, respectively. These results showcase the Corsair EX400U as an excellent choice for content creators and video editors.

Benchmark results in BlackMagic’s Disk Speed Test

The benchmarks I’ve run confirm that Corsair EX400U is a super fast portable SSD with speeds that match its official specifications.

How do you like the Corsair EX400U?

I hope you enjoyed reading this review and found the information about the Corsair EX400U useful. Personally, I’m excited to see USB 4 drives entering the market and offering significantly improved performance compared to previous generations. I’m also curious to see how other manufacturers respond and what portable storage solutions they will develop to compete with the Corsair EX400U. Before I conclude, I’d love to hear your thoughts on the Corsair EX400U. Do you like its design and performance? Are you considering purchasing it? Share your perspective in the comments below.