David Weeks and John Nemo collaborated on this user report.
Products used for our testing and evaluation are:
Seagate GoFlex for Mac Ultra-portable Drive ($150)
Seagate GoFlex Pro for Mac Ultra-portable Drive ($130)
StarTech Thunderbolt Cable ($49)
Elgato Thunderbolt Cable ($60)
Seagate FreeAgent GoFlex Upgrade Cable USB 3.0 ($50)
Seagate GoFlex Thunderbolt Adapter ($100)
Note: Use Seagate’s left column product selection filtering to locate the USB3 cable and Thunderbolt adapter
We also used:
New MacBook Pro with Retina Display and SSD internal drive, a recent MacBook Air with SSD internal drive, and a recent MacBook Pro with both SSD (solid state drive) and conventional internal drives.
Reference: Prior review of Seagate’s two Ultra-portable Mac external drives
Reference: Prior review of Seagate’s two GoFlex Thunderbolt Adapters
David Weeks and I set up shop in his home office for a day of testing and comparing Thunderbolt, USB 3, and FireWire 800 drives, adapters, and cables. Until recently, no stock Macintosh had Thunderbolt or USB 3 capability. Apple appears to be leading the pack, once again, by replacing FireWire 800 ports with Thunderbolt, and by replacing USB 2 ports with USB 3.
Using David’s new MacBook Pro with Retina Display, we copied back and forth many times his 39GB folder containing hundreds of large and small installer files. Your results in a real-world testing situation will vary, but this folder with a range of files will demonstrate typical speed differences between the three transfer protocols under discussion.
With a Seagate GoFlex for Mac Ultra-portable external 5400rpm drive inserted into a Seagate GoFlex Adapter “sled” and connected with a Thunderbolt cable, the transfer took 7:57 minutes. Activity Monitor confirmed a read speed of over 90 MB per second, and a write speed of over 80 MB/s. That is fast, in case you wondered. Remember that duration: approximately eight minutes.
Switching the same Seagate GoFlex for Mac Ultra-portable external 5400rpm drive to a Seagate FreeAgent GoFlex Upgrade Cable USB 3.0 and copying the same file took 8:43 minutes. The read speed varied between 70-100 MB/s, and the write speed was over 80 MB/s. It appears that writing to this drive via Thunderbolt or USB 3 is equally efficient, and the USB 3 drive is slower than the Thunderbolt drive only in its reading process. Remember that duration also: almost nine minutes.
We repeated the tests above with Seagate’s faster 7200 rpm GoFlex Pro for Mac Ultra-portable Drive. We expected this faster drive to have quicker transfer times, but it didn’t. We decided the reason is that my 5400 drive has a cleaner volume structure than my more crowded and fragmented 7200 drive. MyMac’s earlier review of these two similar external bus-powered hard drives recommended the 5400 over the 7200 due to value for money relative to typical usage. If both drives were new and/or uncluttered, the 7200 rpm GoFlex Pro for Mac Ultra-portable Drive would indeed be faster than its 5400 rpm GoFlex for Mac Ultra-portable Drive sibling.
My two-year old MacBook Pro has both a SSD and a conventional spinning hard drive, plus one FireWire 800 port. It’s not possible to do precise comparisons with FireWire versus Thunderbolt or USB 3, because Apple’s lineup of computers does not include MacBook Pros with all three types of ports. Copying our test folder using FireWire 800 onto my SSD took 9:12 minutes. Read speed was 73 MB/s, and write speed ranged between 65-80 MB/s. Remember that duration: slightly more than nine minutes.
Thunderbolt Target Disk Mode
The fastest possible connection is between two internal SSDs, so we used Target Disk Mode to connect David’s new MacBook Pro to his wife Nancy’s MacBook Air. Copying the same 39 GB folder took a rapid 5:55 minutes. Read speed was a blazing 90-120 MB/s, and write speed was 106-110 MB/s. Remember this amazing duration: under six minutes.
Results and recommendations
We could convert all these minutes and seconds to seconds for a linear mathematical ratio comparison, but by now you know that our tests are conclusive.
USB 3 is a little faster than FireWire 800, but the difference is not large enough to convert all your computers and drives and cables and adapters from FireWire 800 to USB 3 just because of the potential speed increase.
Thunderbolt is faster than both USB 3 and FireWire 800, but again unless you change computers you don’t need to alter your equipment or data transfer methods if you are happy with a non-Thunderbolt environment. Thunderbolt cables are very expensive, regardless of manufacturer and length.
Apple just released an inexpensive Thunderbolt to FireWire Adapter, which will ease the transition for millions of Macintoshers.
The future does not include FireWire, so prepare yourself mentally and financially for your new best friends: Thunderbolt and USB 3.