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A funny thing happened on the way to work today… No really… We have a pile of high end and super fast portable SSDs waiting to be reviewed and we were not happy learning that motherboards with USB 4 typically do not provide full USB4/Thunderbolt 4 data transfer rates. Yes, we can surpass that of the Thunderbolt 3 speeds of 2.8GB/s and even get as high as 3.2GB/s, but for some reason, motherboards with USB4 and Thunderbolt 4 simply don’t want to reach higher. So it was time for a new build which we will get to…
For now though, we will speak to our review for today which is Corsairs newest EX400U USB4 Portable SSD. This SSD is available in 1, 2 and 4TB, is USB 4.0 and is able to achieve performance as high as 4GB/s read and 3.6GB/s write for the 2/4TB versions. The 1TB version drops just a bit to 3.5GB/s read. All come with a three year warranty and MSRP pricing is listed as $139.99 (1TB), $199.99 (2TB) and $359.99 (4TB). Check Amazon pricing now.
The Corsair EX400U is 2.5″ square, just under 1/2″ thick, weighs just over 3oz and is constructed of an aluminum top and plastic sides and back. It is USB-powered by its own 40Gbps Type-C to Type-C cable, and contains the Phison PS2251-21 40Gbps USB4 portable SSD controller with KIOXIA TLC memory. Buyer beware. There are similar products on the market right now, none of which contain these quality components.
The Corsair EX400U is fully backward compatible to USB 3/2 but, in order to achieve performance at the level we are going to demonstrate today, it must be connected to a USB4/Thunderbolt4 or higher system. A very unique characteristic of this SSD is that it contains a round white metal magnetic ‘Magsafe’ connector on the back which allows secure connection to a Magsafe device, or anything else that’s metal…such as our new Corsair 6500x Dual Chamber case.
The Corsair EX400U uses 4.5W active read, 4W active write, is not listed as being waterproof but is described as being 1500g shock resistant. It is compatible with Mac 13 and newer devices along with Android and PC and its features include SMART, TRIM and garbage collection.
With respect to performance, the system we are using today is ThunderBolt 5 (80Gbps) so it returns full performance at 4000MB/s, regardless of whether it is Thunderbolt 4/USB4 or higher. Having a USB4 device (40Gbps) does not guarantee you will get full USB4 speeds as we found out and described earlier. Believe it or not, you are more likely to get full speeds from a USB4 laptop than PC. If you plug this into a USB 3.2 2×2 (40Gbps) Type-C port, you will get 2000MB/s performance and anything lower will return 1000MB/s speeds.
Let’s jump into things just a bit deeper on the next page.