Apple yesterday released AirPort Client Update for MacBook and MacBook Pro, addressing issues with AirPort performance on OS X 10.5.8 while running on battery power.
This update is recommended for some Intel-based Macintosh computers running Mac OS X v10.5.8 and addresses an issue with AirPort performance while running on battery power. It may only be installed on:
MacBook (13-inch, Late 2007)
MacBook (13-inch, Early 2008)
MacBook (13-inch, Late 2008)
MacBook Pro (15-inch, Early 2008)
MacBook Pro (17-inch, Early 2008)
MacBook Pro (17-inch, Late 2008)
A number of users in Apple's discussion forums had reported substantial speed drops and latency increases over Wi-Fi when running on battery power after applying the OS X 10.5.8 update released last week, and this AirPort update appears to address those specific issues. The update weighs in at 1.68 MB and requires OS X 10.5.8.