updated 12:25 pm EST, Mon November 17, 2008
USB 3 Final Spec
The USB 3.0 Promoter Group today revealed the full specifications for its namesake interface standard and so greenlit development of computer platforms and devices using the technology. The new peripheral format will now officially peak at 5Gbps, or about ten times faster than the 2.0 protocol. In actual tests, 25GB of data transfers in nearly 14 minutes over USB 2.0 but just 70 seconds over USB 3.0, significantly outpacing FireWire 800 as well as many hard drives.
Some of the often-cited other limits of USB versus FireWire have also been tackled in the official 3.0 release. While it consumes less power overall, the spec also lets USB 3.0 push more power from the host to an attached device and should result in fewer external hard drives or other add-ons that need a separate AC power source to run properly.
USB 3.0 is backwards-compatible with USB 2.0 hardware but won't work with USB 1.0 devices due to significant changes between the original format and its third generation, which comes more than ten years later.
Hardware that supports USB 3.0 is still distant and won't show until the second half of 2009, when device controllers that can recognize and use the format are available. End devices also aren't due until 2010.
FireWire isn't remaining static and should be upgraded to the S3200 standard ahead of USB 3.0 to provide about 3.2Gbps of bandwidth and similar power management features.