Apple and Intel's Thunderbolt interface finally has a drive you can afford. The Seagate GoFlex Thunderbolt Adapter ($99 list) is an add-on accessory for Seagate's successful GoFlex portable hard drive line. The Thunderbolt adapter lets you make the most of the speedy 10Gbps (theoretical) interface found on new iMacs, Macbooks, and Mac minis. Grab a high-capacity Seagate GoFlex drive and one of these sleds, and you'll have the fastest hard drive you can buy for under $1,000. Photo editors, large file copiers, video producers, and rabid Mac enthusiasts, rejoice!

Design and Features
The GoFlex Thunderbolt Adapter is essentially a black plastic sled that clips onto your Seagate Goflex portable drive. It will work equally well with the Seagate FreeAgent GoFlex Ultra-Portable ($99.99 list, 4.5 stars), Seagate GoFlex Ultra-Portable for Mac ($219.99 list, 3.5 stars), and Seagate GoFlex Pro, which we used to test the adapter. It will connect to the Seagate GoFlex Slim ($99.99 list, 4 stars), but since that drive is slimmer than the others, it will hang less securely in the sled. The other GoFlex drives fastened securely to the Thunderbolt adapter. Unlike the basic GoFlex USB and FireWire adapters, the Thunderbolt Adapter has its own little logic board in it, necessitating a full-length chassis (about five inches long) that's perforated for cooling. The sled adds about a centimeter to the drives' thickness. There is a single Thunderbolt port on the adapter, so you can't daisy chain the adapter to another drive: this has to be the last device on the chain. Another nit is that the Thunderbolt cable itself isn't included; you'll have to buy Apple's $49 Thunderbolt cable to use the adapter. Seagate says it's working with suppliers to source another Thunderbolt cable in the future. That said, the GoFlex Pro clipped to the drive securely; I wouldn't worry about leaving it clipped to the adapter while in my travel bag.

View All 8 Photos in Gallery

The adapter will work with the drive formatted to any format (FAT32, NTFS, HFS+), but for testing purposes we reformatted the drive from NTFS to HFS+, the native Mac file format. The Thunderbolt Adapter has two status lights on it, letting you know that the drive is successfully connected to the computer, as well as letting you know about drive activity. It's best to use a 7,200 rpm or faster drive with the adapter, since Thunderbolt is such a fast interface.

Performance
The Thunderbolt interface gives any drive added performance, but this is the first time we've looked at a relatively pedestrian drive, one that doesn't cost upwards of $1,000 (or more) like the Promise Pegasus R6 ($1,999 list, 3.5 stars) and the LaCie Little Big Disk Thunderbolt (240GB SSD) ($899.99 list, 4 stars). The GoFlex Pro with the Thunderbolt interface took a brisk 13 seconds to transfer our 1.2GB test folder, which smokes the USB 2.0 interface on the same MacBook Pro (43 seconds). For kicks, we hooked the GoFlex Pro up to our Windows 7 testbed via the drive's USB 3.0 port, and it was slower (17 sec). To put this into perspective, the LaCie drive took 11 seconds to transfer the same folder, using two internal hard drives to share the load over the Thunderbolt interface. Pure throughput was a little slower on the drive; it returned good numbers on the AJA System test (100MBps Read; 90MBps Write), though they were quite a bit slower than the LaCie (476MB/sec Read, 252MB/sec Write). To put that into perspective, the GoFlex Pro returned a third of the performance under USB 2.0 (37MBps Read, 30 MBps write). Essentially, you will notice a speed increase using the Thunderbolt adapter for normal operations, but if you're a video editor on an up-to-the-minute deadline, the more expensive drives will pay off.

If you're a new Mac user who wants to use that speedy port marked with a lightning bolt, then get a Seagate GoFlex drive with the Seagate GoFlex Thunderbolt adapter. It'll give you a speed boost far over the USB 2.0 and FireWire 800 you're used to. It's a lot cheaper than the LaCie and Promise drives that have the interface built in, though those drives have their place, (like for users who need to edit Peter Jackson's latest Middle Earth adventure in real time). For everyone else, be they photo professionals or the budding video auteur working on a student project or just hardcore Mac enthusiasts, a GoFlex drive with this adapter is more than enough to keep them happy. It's fast.

COMPARISON TABLE
Compare the Seagate GoFlex Thunderbolt Adapter with several other hard drive side by side.