From the start, Seagate's GoFlex range of external hard drives had a range of connection options that could fill just about any computer port. With a snug clip-on adaptor, you could transform Seagate’s FreeAgent Ultra-portable hard disk into a USB 3.0 drive, FireWire 800, or eSATA. There was even an adaptor that turned the disk into network storage, via an ethernet-ported controller dock. Read more portable hard storage reviews.

Following the building popularity of Thunderbolt I/O developed by Intel and Apple, Seagate now has a GoFlex Thunderbolt adaptor to match.  

This new take on the adaptor theme is remarkably larger than the end-cap style convertors for USB, FireWire and eSATA. It comprises a sled-like board that sits under the attached drive; inside this underbelly are the essential electronics that translate between a hard disk's SATA language and the PCI Express protocol of Thunderbolt. 

It takes up far more space than equivalent circuits for other drive types, in part because Thunderbolt is not yet a mature technology, and several different chipsets are required to make that link. Future convertors of this type are likely to be smaller and, crucially as we discovered, consuming less electrical power from the Thunderbolt bus. 

Note that is only features a single Thunderbolt port. This is standard for bus-powered Thunderbolt devices, but it does mean you can only mount the GoFlex drive at the end of a Thunderbolt chain, not in the middle. Read reviews of Apple Mac computers.

The range of Segate GoFlex Ultra-portable disks is designed to slot into this dock: 320GB, 500GB, 750GB, 1TB and 1.5TB capacity units. We tested the GoFlex Thunderbolt with the chunky 1.5TB drive; at present though, only the smaller drives seem to be readily available in the UK.

The GoFlex Thunderbolt adaptor is constructed from tough-feeling matt black plastic. No screws are visible; instead a rubber non-slip footplate that’s secured by adhesive appears to be covering access to the electronics inside. 

Seagate GoFlex Adapter Thunderbolt: Performance

Thunderbolt is a very fat pipe in terms of its potentia throughput, especially by the standards required of the 2.5in notebook SATA disk that lives inside every GoFlex Ultra-portable case. 

Unlike USB 2.0, or even FireWire 800, the Thunderbolt interface should never get in the way of performance – the only limiting factor in file transfer speeds should be now the internal drive itself.

We tested the GoFlex Thunderbolt using Blackmagic Disk Speed Test on an Apple MacBook Pro Retina. The app measures disks' ability to maintain reliable high-speed datastreams for video delivery. 

Here the GoFlex Thunderbolt could sustain sequential transfers of 90MByte/sec. We also checked with the USB 3.0 adaptor in the same setup, and here too we saw circa-90MByte/sec read and write speeds.

With Thunderbolt's theoretical speed of 10Gbps, as well as USB 3.0 specified up to 5Gbps, it's no surprise that the SATA disk could easily reach its peak performance.

The Seagate GoFlex adaptors can be far more versatile though, able to accept naked standard-issue 2.5in SATA drives, disk or solid-state. And it's by slotting in a third-generation SATA 6Gbps solid-state drive that we really stretched both Thunderbolt and USB 3.0 adaptors to their actual limits. 

Using a Patriot Wildfire 240GB, a third-gen SATA solid-state drive, the USB 3.0 GoFlex adaptor was found to peak at 106MByte/sec for writes, and 163MB/s for reads.

Using the same SSD plugged into the GoFlex Thunderbolt adaptor, we saw writes and reads up to 146MB/s and 163MB/s respectively. 

We did experience some disconnections when using the Patriot SSD, most likely due to peak power demands of the drive exceeding a strict limit provided by available current on the Thunderbolt power bus.

Both adaptors fell short of their respective standards’ available performance. But neither Seagate’s Thunderbolt nor USB 3.0 adaptors will be any hindrance to performance when using the system as designed with Seagate's matching GoFlex Ultra-portable disk drives.

Seagate GoFlex Adapter Thunderbolt review: Specs

  • Hard drive adaptor
  • 1x Thunderbolt port
  • 75 x 123 x 28.5mm
  • 94g (355g with 1.5TB drive)
  • Hard drive adaptor
  • 1x Thunderbolt port
  • 75 x 123 x 28.5mm
  • 94g (355g with 1.5TB drive)

OUR VERDICT

The Seagate GoFlex Thunderbolt adaptor is a simple, ingenious attachment that allows speedy access to data on a GoFlex Ultra-portable drive. It also works with unboxed 2.5in SATA drives although not necessarily with all bare SATA Revision 3.0 SSDs that have higher power requirements. Apple is the leader in Thunderbolt-enabled PCs, making this Thunderbolt adaptor of particular interest to Mac users. However, since a June refresh most current Macs are now also equipped with USB 3.0, making the market for this unit already dwindle – at £99.95, it's over twice the price of the USB 3.0 adaptor, so will be of most interest to owners of 2011 Thunderbolt-only Macs. Nevertheless, it’s a useful additon to Seagate’s versatile GoFlex storage range.

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