By The compact, blue-striped SC735 from Adata is a stylish, if slightly more compact, version of the hyper-portable SSD, sometimes known as a thumb drive. It is a 10 Gbps USB and comes with up to 2 TB at remarkably low prices. The drive is not slow, but it performs poorly, particularly when writing larger amounts of data. This is our only major warning.
Features
I still think of “thumb drive” when I use the SC735, even if it’s not the conventional shape. Though the overall dimensions are nearly the same, it is significantly shorter and wider than conventional thumb drives, measuring around 0.4 inches thick, 2.25 inches long (2.5 inches with the Type-C connector extended), and 1.2 inches across. At under half an ounce, the weight is barely noticeable.
Retractable connections often don’t appeal to me because they often retract when you don’t want them to, are difficult to move, or don’t remain in place. Fortunately, none of those problems affects the SC735’s retractable design. The sliding switch locks securely into position and is located on the bottom to prevent disruption when you hold the device by its sides, which is by far the most comfortable method.
Nevertheless, the SC735 wobbles slightly when the slide is facing down, as the slide button protrudes slightly. One “side” of the SC735 is flat to make up for this, so you can place the drive on that side (or the other bottom, if you’d like) without it wobbling.
Adata warrants the SC735 for five years—two years beyond the norm, though the company doesn’t provide a TBW rating. However, QLC of this apparent vintage (see the performance section) is typically rated at 250 TBW per terabyte of capacity. TBW stands for TeraBytes Written, or more informatively, TeraBytes that may be written before you can’t write anymore.
Although Adata does not offer a TBW rating, the SC735 is covered by a five-year warranty, which is two years longer than the standard. However, according to the performance section, the QLC of this apparent vintage is typically rated at 250 TBW per terabyte of capacity. TBW is an acronym for TeraBytes Written, or more accurately, TeraBytes that may be written before you are unable to write.
Price
The SC735 costs $80 for the 1TB model and $150 for the 2TB model. A bare internal M.2 NVMe SSD with the same capacity would cost much less than that. These are incredibly cheap prices for an external 10 Gbps SSD.
Performance
As long as you don’t write too much data to the SC735 at once, its performance is sufficient. Although it’s by no means the quickest 10Gbps SSD we’ve tested, you wouldn’t be able to detect the difference under typical use. However, the SC735 lags—from a little to a lot—when writing massive amounts of data. Even our 2TB model ran out of secondary cache before finishing the 450GB write, and our 48GB write tests yielded no noteworthy results.
The SC735 was comparable to most 10Gbps drives in CrystalDiskMark 8’s sequential tests, but it wasn’t quite on par with the excellent, albeit more expensive, Corsair EX300U or Teamgroup X2 Max, which I compare it to (quite unfairly). The SC735’s QLC native write rate of only 130MBps, or around the speed of a 2.5-inch USB hard drive, was the reason it fell so far behind in the 450GB write (shown in the following chart).
Up until recently, this was the standard for QLC; more modern versions are now available that can handle native writing speeds of about 500 MBps. The SC735’s write time would have been comparable to the others in the absence of the slowdown. Remember that we evaluated the 2TB capacity (the competitors were likewise 2TB). The 1TB SC735 will finish even further behind and run out of secondary cache in half the time. For every SSD, capacity dictates the amount of secondary cache that is available.
Conclusion
The SC735 has many advantages, including a nice appearance, a creative design, and very competitive pricing. If you don’t try to write too much at once, performance is also sufficient.
