MSI DATAMAG 20Gbps Magnetic Portable SSD Review

You don’t need an iPhone to use this

USB 3.2 Gen2x2 may have not been as widely adopted as it could have been in the past few years, but there are some very fast portable SSDs out there which take advantage of that 20Gbps connection. We looked at Samsung’s Portable SSD T9 a year ago, and today we have an interesting new Gen2x2 portable from MSI – the DATAMAG 20Gbps.

Sure, the primary selling point of this drive is its magnetic adhesion to devices like the most recent iPhone models (MSI mentions the iPhone 15/16 Pro and Pro Max), but it can stick to anything metal – including the stick-on metal discs MSI includes in the package. I immediately came up with an installation scenario that made full use of the magnetism, but I was more interested in finding out how fast it was.

The DATAMAG 20Gbps

This 81 gram, 66 x 66 mm square, 13 mm thick device is powered by a PHISON PS2251-U18 controller, which is an interesting single-chip solution that requires no bridge controller.  It comes with two flat USB-C cables of different lengths (one very short), and feels solid in hand. We tested it on our current AMD testbed, which features the nearly unobtainable Ryzen 7 9800X3D processor on a Gigabyte X870E AORUS ELITE WIFI7 motherboard.

Here’s a look at synthetic benchmark results:

Data transfer speeds exceed the advertised numbers, with sequential reads of up to 1.66 GB/s in CrystalDiskMark at default settings, and up to 1.83 GB/s using ATTO Disk Benchmark (MSI specifies up to 1600 MB/s). Sequential writes were 1.52 GB/s with CrystalDiskMark and 1.67 GB/s with ATTO (MSI specifies up to 1500 MB/s).

Of course these are best-case numbers, but at least validate the performance which is rather conservatively advertised by MSI – as evidenced by the graphic below (which calls out the limited test duration and use of a 4GB file):

In real-world testing file transfers of 4GB or less met the advertised speeds, but when moving up to larger test files we saw speeds fall back to 10 Gbps speeds. An 8GB test file saw greatly reduced transfer rates after the initial burst speed, leading me to suspect that some form of cache is at play (and considering that the Phison controller is DRAM-less it may be an SLC cache on the NAND).

As you can see from the screenshots in the gallery, sustained transfer rates of ~800 MB/s read and ~500 MB/s write in 16GB (2x 8GB) file copy tests are pretty good, but file transfers under 4GB will be far more impressive, and can take full advantage of the 20 Gbps capabilities of this product.

Magnets and Final Thoughts

And now for the “killer” feature of the DATAMAG 20Gbps, and the real reason to consider this product. Now, one may ask if a magnetic ring attachment offers anything to non-iPhone users, and I would answer, of course it does! But I didn’t bother with the included metal rings since I already had a metal object in mind. Namely, my case. Here’s a quick before and after shot:

First of all, I know it’s bad to let a portable drive just hang from the USB cable, and I have done this on several occasions (don’t act like you haven’t done it! Ok, just me?). Anyway, thanks to the mysterious properties of magnets, I could position the DATAMAG 20Gbps drive exactly where it would be out of the way, and with zero stress on the cable. And the longer cable it comes with would offer even more placement flexibility on your case.So, is this a practical product? I think so, considering that it’s quite a bit like small SSD offerings we have seen from the likes of Crucial, but with the additional utility of magnetic attachment. I don’t know pricing yet, and can’t even find this on sale anywhere, but MSI has sampled a number of outlets (including this one) leading up to the launch, so maybe we will see it before Christmas.

The value proposition will have a lot to do with our conclusion, naturally, so for now I will simply say that it can be a very fast drive, but larger file transfers slow it down to 10Gbps speeds (on our X870E board, anyhow).