Glyph Atom EX20 SSD review: Fast 20Gbps USB (if you BYO cable)
At a glance
Expert rating
Benefits
- Fast 20Gbps performance (with better cable)
- Great weight and silicone sheath
- Beautiful
Disadvantages
- The included cable is of inferior quality
- Very, very expensive
Our verdict
Considering the high price of this SSD, it should come with a better cable.
Price when reviewed
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Best prices today: Glyph Atom EX20 20Gbps SSD
$309.99
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This boutique USB SSD from Glyph is one of the most impressive recently deployed in our lab. In terms of design and performance, this is a good thing, but the price is also incredibly high. This is more than likely due to the continued rise in NAND prices, which particularly affects the entire storage sector.
Read on to learn more, then check out our roundup of the best external drives for comparison.
What are the features of the Glyph Atom EX20?
The Atom EX20 is an exceptionally good-looking USB 3.2×2 (20Gbps) external SSD from Glyph. It is completely black and covered with a silicone sleeve ribbed in a tread pattern to provide a very secure grip.
At 7.5 ounces (jacket included), the Atom EX20 isn’t the lightest external SSD I’ve tested, but its weight also gives you a sense of quality. It measures, including jacket, about 4.4 inches long, 2.4 inches wide, and just under an inch thick. The Type-C port and activity light are on the same end of the unit, with the port offset to the left.
The Atom EX20 comes with a three-year warranty with two years of data recovery and one year of replacement. There is no TeraBytes Written (TBW) classification, but figures around 600 TBW, which is a lot of data. Remember that reads don’t count, only writes.
How much does the Glyph Atom EX20 cost?
SSD prices have gone up a bit recently, but I was still a little surprised by the Atom EX20’s rather high price for a 20Gbps SSD: $310 for 1TB, $420 for 2TB, $700 for 4TB, and $1,500 for 8TB. And the prices we show are discounts, as shown below.
Basically, these prices are more in line with a faster 40Gbps USB4 than a 20Gbps USB 3.2×2. With that in mind, the 40Gbps and only slightly more expensive Glyph Atom EX40 (see review ahead) is the better deal.
Note that the 40 Gbps version of the OWC 1M2 case currently only costs $90 and can be married to an NVMe SSD for less than $300. You can also wait six months to see if the AI/data center bubble bursts and SSD prices drop.
Glyph Atom EX20 Performance Caveats
Using the included 7-inch Type-C cable caused issues on our Windows benchmark, with the EX20 initially writing at just 50-80MB/s and writing at just 20MB/s on an M4 Mac. For some reason, read performance exceeded 2 GB/s, so the cable problem is a particularly thorny conundrum.
If you want the best, least problematic Type-C cable, use a Thunderbolt cable: they’re fully compatible with USB and manufactured to tight tolerances. Indeed, using one solved the Atom EX20’s write performance problem.
This isn’t the first time I’ve used a bundled cable that doesn’t provide optimal performance: the TerraMaster D1 SSD Pro had the same problem, even though it was an 80Gbps cable limited to 20Gbps.
Also note that as with all USB 3.2×2 SSDs, the Atom EX20 will drop back to 10Gbps without a dedicated 20Gbps port. This is because most non-protocol systems do not support the protocol, but do support USB 3.2 Gen 2 at 10Gbps.
How fast is the Glyph Atom EX20?
Once I switched cables, the 4TB Atom EX20 delivered stunning performance. The one that earned it second place among all 20 Gbps SSDs. The only drive that managed to beat it was the Asus TUF Gaming A2, which is actually an empty case that I filled with a blazingly fast Samsung 9100 Pro.
It wasn’t particularly fair of us. It’s for this reason that we consider the EX20 to be the best when it comes to pre-populated 20Gbps USB. This is confirmed by the drive’s CrystalDiskMark 8 numbers shown below.
The Glyph Atom EX20 once again competed against its rivals (Corsair EX400U, Crucial X10) in the CrystalDiskMark 4K tests.
The Atom EX20 was competitive in our real-world 48GB transfers, although it didn’t show as much potential in FastCopy testing as the Crucial X10.
Being a 4TB SSD certainly helped the Atom EX20 in our 450GB write test (the others are 2TB). It had plenty of secondary cache to play with and never slowed down significantly.
I have no complaints about the performance of the Atom EX20: it’s a very fast 20 Gbps USB SSD.
Should you buy the Glyph Atom EX20?
In light of my experience with the cable and the price, the purchase recommendation is… maybe. If cost is not a concern, answer yes. In other words, the design and performance are excellent (except for the cable), but at the moment it’s very expensive, as are many SSDs from specialist vendors.
Note that Glyph is investigating the cable issue and will likely resolve it by the time you read this. That said, test yours first using CrystalDiskMark 8 or another synthetic benchmark to make sure.
How we test
Drive testing is currently using Windows 11 24H2, 64-bit running on a Samsung 990 Pro PCIe 4.0 in an Asus Z890-Creator WiFi (PCIe 4.0/5.0) motherboard. The CPU is a Core Ultra i5 225 powered by two Crucial 64 GB DDR5 5600 MHz modules (128 GB of memory in total).
20Gbps USB and Thunderbolt 5 are integrated into the motherboard and Intel CPU/GPU graphics are used. The internal PCIe 5.0 SSDs involved in testing are mounted in an Asus Hyper M.2 x16 Gen5 adapter card located in a PCIe 5.0 slot.
We run the CrystalDiskMark 8.04 (and 9), AS SSD 2, and ATTO 4 synthetic benchmarks (to reduce article length, we only report the first) to determine the potential performance of the storage device. Next, we run a series of 48GB transfer and 450GB write tests using Windows Explorer drag and drop to show what users will see during routine copy operations, as well as running FastCopy much faster as administrator to show what’s possible.
A dual 25GB/s SSD RAID 0 array on the aforementioned Asus Hyper M.2 x16 Gen5 is used as the second drive in our transfer tests. Previously, 48 GB tests were performed with a RAM disk used for this purpose..
Each test is performed on an NTFS and newly TRIM formatted drive so that the results are optimal. Note that in normal use, as a disk fills up, performance may decrease due to less NAND for secondary caching, as well as other factors. This problem has eased somewhat with the current generation of SSDs using more mature controllers and much faster latest generation NAND..
