Apple said the fixes a problem reported by "a small number of customers" using drives based on the latest SATA specification with the , released this month.
But Apple warned that it has not shipped drives operating at the higher-speed specification, saying, "While this update allows drives to use transfer rates greater than 1.5Gbit/sec, Apple has not qualified or offered these drives for Mac notebooks and their use is unsupported."
Apple interface on its most recent MacBook Pro laptop models, moving from a 3Gbit/sec. interface to 1.5Gbit/sec.
Most industry observers Computerworld spoke to speculated that the MacBook Pro line was experiencing higher than acceptable data error rates related to the 3Gbit/sec. SATA interface.
Apple has yet to respond to multiple requests for information about the reason for its SATA downgrade on the MacBook Pro.
Meanwhile, that Apple has also issued an for 20-inch and 24-inch early 2009 iMacs, which fixes problems where machines using ATI Radeon HD 4850 graphics cards would intermittently stop responding, as well as issues with waking from sleep while in Boot Camp.