Ever since Thunderbolt was introduced last year, we’ve had users asking for our drives to feature it. While Thunderbolt is truly a remarkable interface that opens a lot of expansion options, the main two reasons cited are speed and flexibility. With the addition of USB 3.0 to the new Macs, though, some users may want to consider a USB 3.0 option vs. a more expensive Thunderbolt drive for their external storage needs.
One of the most common requests for Thunderbolt is because of speed. Thunderbolt can run at 10Gbps, twice the USB 3.0 maximum of 5Gbps. Unfortunately, most single-drive solutions top out the speed of the drive mechanism itself, which is usually around 1.1Gbps for platter-based drives.
Of course, that’s all in theory. We decided to check out the Buffalo Technology MiniStation Thunderbolt drive, and see how its USB 3.0 performance stacked up to the same via its Thunderbolt connection. We tried both 5400rpm and 7200rpm drives, just to see if we got any difference in performance.
As expected, even though USB 3.0 has a lower theoretical maximum, it is capable of handling the maximum drive speed, so there’s not much of an advantage for Thunderbolt there. And these tests also confirmed what we said in an earlier post regarding drive speeds.
In other words, it doesn’t matter that you’re on the Autobahn if you’re driving a Volkswagon Bus; you’re just not going to be enjoying the full speeds traveling that route promises.
That’s not to say Thunderbolt isn’t a perfectly good connection interface. You’ll certainly see a benefit with Thunderbolt with a much more expensive RAID unit, or even a solid-state drive in an external enclosure. In fact, we tried the latter, testing both one of our 3G SSDs and an OWC Mercury Electra Pro 6G SSD in the same Buffalo unit. It was only once we started adding SSDs to the mix that we began to to see an advantage for Thunderbolt in terms of speed.
For many users, though, this sort of setup is overkill; high-throughput rigs are more for professional applications, such as large Video, Audio, or Graphics workstations that transfer a lot of data back and forth, and these setups—due to either having multiple platter-based drives or high-capacity SSDs—tend to have the “professional” prices to match.
For typical, everyday storage and backup needs, a platter-based external drive connected via USB 3.0 is still going to give you the best capacity and performance for the price.
The other feature of Thunderbolt that entices many is its flexibility. Thunderbolt allows you to attach your displays, drives, and even breakout boxes, such as the OWC Mercury Helios, that allow you install other expansion cards all via a single interface. With storage, though, this can actually be more of a hindrance.
Thunderbolt can only bus power a drive if it’s the only bus-powered device on the chain, and it needs to be at the very end. It’s a limited-power connection as well; many drives (including many 6Gb/s SSDs), can’t be bus-powered via Thunderbolt, as they draw too much power.
Another part of flexibility is cross-system use. You can only use Thunderbolt devices with other Thunderbolt equipped computers. USB 3.0 isn’t nearly as restrictive. With its backward compatibility, you could even hook it up to an original iMac and still have it work.
Thunderbolt is a great interface, and has a lot going for it, especially in terms of expansion options for machine models that didn’t have it before. For some users though, who just need an external drive like an Elite Pro mini for their usual backups and to store extra files, USB 3.0 will suit you just as well as – if not better than – Thunderbolt…while saving you a considerable amount of money.