USB flash drives have had many adjectives used to describe them: portable, handy, easy, ubiquitous. One word we’ve never used to describe them though, is fast. At first this could be attributed to the NAND flash cells used; flash memory was pretty slow initially. As the recent crop of SSD’s has shown however, that’s no longer an issue. These days, the biggest thing holding a flash drive back is the bus it uses to talk to the system.
USB 2.0, the currently most widespread iteration of the standard, has a theoretical maximum throughput of 480Mbit/sec. Other factors in the standard’s design—including the bandwidth allocation model used by the host controller, transfer overhead, and the number of other devices present—all combine to lower the effective throughput by quite a bit. As you’ve seen in hardware reviews here and elsewhere, the most you can realistically expect out of a USB 2.0 drive is ~40MB/sec. This has made them an effective replacement for removable media such as floppies and optical discs in sneakernet scenarios, but nobody’s going to confuse them for primary storage.
Enter USB 3.0. Designed once again by the group of companies known as the USB Implementer’s Forum (USB-IF), this latest revision to the standard gives us a total of four signalling rates:
- Low-Speed, which transfers data at 1.5Mbit/sec. Originally defined in the USB 1.0 spec, this is the rate most often used by mice, keyboards, and other low-bandwidth input peripherals.
- Full-Speed, which transfers data at 12Mbit/sec. Introduced in the USB 1.0 spec, this is the mode originally meant for external CD drives, scanners, printers, and other data-hungry devices.
- High-Speed, which transfers data at 480Mbit/sec. Introduced in the USB 2.0 spec, this is the transfer speed we’re all most familiar with these days. When a device is said to be “USB 2.0 capable”, this is what most of us think of.
- SuperSpeed, which transfers data at 4800Mbit/sec. This is the new signalling rate introduced by USB 3.0.
There is some confusion regarding these transfer rates and the USB specification revisions, which I’ll attempt to clear up here. All USB devices of whatever speed are certified using the latest revision of the USB specification at the time the device is made. This means that everything from mice and keyboards on up to top-end SSD’s will be “USB 3.0 certified” from this point forward. The signalling rate descriptors (low-speed, full-speed, high-speed, SuperSpeed) are what tell you how fast the device is allowed to go.
Another important point is that USB 3.0 SuperSpeed devices, in order to reach their full potential, have to be used with USB 3.0 SuperSpeed ports on your motherboard and USB 3.0 SuperSpeed cables. If you plug a USB 3.0 SuperSpeed device into a USB 2.0 port, you’ll get USB 2.0 performance. Same deal if you use a USB 2.0 cable. The cables and ports are easy to tell apart; USB 3.0 SuperSpeed ports and cables have bright blue plastic tongues under the pins, while USB 2.0 and older ports do not. Furthermore, USB 3.0 SuperSpeed cables will plug into USB 2.0 hubs, but not into USB 2.0 devices.
|USB 3.0 SuperSpeed Logo. If you don’t see this logo or the phrase “USB 3.0 SuperSpeed” on the device’s packaging, it won’t give you the full SuperSpeed performance.|
So What’s the Point?
As you have probably guessed by now, all of this is a preamble to discussing the latest and greatest USB flash drive from Patriot Memory, the Patriot SuperSonic 32GB. Taking advantage of the extra bandwidth afforded by the USB 3.0 SuperSpeed bus, this drive promises speeds faster than what most hard drives can deliver. Can it make good on those claims? Let’s find out.