It's been more than a year since I initially looked at USB 3.0 as it relates to portable external storage, and many more devices have hit the market. More importantly, we're finally seeing some notebooks that include USB 3.0 ports (some call them SuperSpeed ports) on them, eliminating the need for users to connect the drive through an ExpressCard slot.
To see whether the drives and speeds have improved, I gathered up a bunch of the latest USB 3.0 portable external drives and ran them through some benchmarking and "real world" tests. Like my earlier tests, USB 3.0 speeds are about 2x to 3x faster than USB 2.0 slots, but still not "10x faster" as some vendors are claiming. Still, a 2x to 3x jump in speed can mean a lot of time saved when transferring large amounts of data between your computer and the drive.
For our tests, we received the Buffalo MiniStation Cobalt USB 3.0 portable hard drive (640GB capacity); the Iomega eGo (1TB capacity); the LaCie Rugged USB 3.0 All-Terrain Hard Disk (500GB capacity); the Seagate GoFlex portable hard drive (1.5TB capacity); the Toshiba Canvio 3.0 Plus (1TB capacity) and the WD MyPassport Essential SE (1TB capacity). We also performed a baseline test on the internal hard drive of our test notebook, an HP Envy 17 (450GB capacity) running Windows 7.
We ran three benchmarks to get data on read and write speeds - we used CrystalDisk Mark 3.0.1 x64, Atto Benchmark Disk Benchmark V 2.46, and a "real-world" file-size test, in which we dragged-and-dropped a folder from the notebook's hard drive to our external drives. In addition to testing with the USB 3.0 cable and port, we also ran tests on a USB 2.0 port on the same notebook.
When using the USB 3.0 port, all of the drives were significantly faster than the USB 2.0 port - with the benchmarks, we saw a range of 81M to 96 MBps on read speeds, and between 54M to 58 MBps on write speeds. In our "real world" tests, we saw ranges between 38M to 49 MBps (basically write speeds).
Comparing between USB 2.0 and 3.0, we saw that USB 3.0 was between 2x and 3x faster, with some drives able to achieve more than 3x speeds in our tests. For example, the Buffalo MiniStation Cobalt unit could achieve about 30.10 MBps via the USB 2.0 port, but jumped to 95.67 MBps when attached to USB 3.0. One quick thing to remember, then, is to make sure you are connected to the USB 3.0 port to achieve these faster speeds - on the ENVY 17 notebook, the USB 3.0 port was separated from the other USB 2.0 ports (it's easy to forget that).
I was unable to achieve the 10x factors that some of the vendors are advertising on their packages. Iomega, for example, has a 10x logo on its eGo box, with the "Up to" caveat when explaining its USB 3.0 vs. 2.0 speeds. Buffalo claims that its TurboPC technology offers "up to 135% faster transfer speeds" than other USB 2.0 hard drives, and that's pretty conservative - in our tests, we got more than 200% faster.
The other cool part about the latest USB 3.0 devices: these speeds are approaching that of the internal hard drive. Our baseline with the internal drive was able to get read speeds of between 100M and 103MBps, and write speeds of about 100MBps. The big difference between internal vs. external, however, is in the write speeds. But at the read speed level, they are pretty close. A Seagate spokesman said that buffering going on behind the scenes helps speed up the read from the drive - and that when writing, there is more overhead from the drive that tends to slow it down. Other factors include the types of components on the PC side, as well as the drivers used, the spokesman said.
Of course, speeds and feeds shouldn't be the only factor in deciding between drive A and drive B in this space. Vendors try to differentiate themselves by adding software to their drives, or in the case of LaCie, by adding rugged protections and other design elements.
All of this discussion of USB 3.0 may not matter anyway, with the advent of Intel's Thunderbolt technology (not to be confused with the HTC ThunderBolt smartphone, now on Verizon's network), which is found in the new line of Apple MacBook Pro laptops. If Thunderbolt finds its way onto PC notebooks and systems, then all this talk about 2x, 3x or 10x basically goes away. But until (or if) that happens, USB 3.0 is a good way to get faster than what you're currently using.