hdapm
 
A Mac OS X command line utility for setting the power management (APM) level for ATA hard drives.
   
  It can be used to:
  • eliminate "clicking when idle" noises exhibited by some laptop hard drives
  • make a drive save more power and spin down more aggressively that in does with the default OS settings.
 

Compatibility

MacOS 10.4 or 10.5. ATA/SATA hard disk with APM support. Does not work with USB or Firewire attached drives.

 

Downloads
Updated 2007-12-09

Binary disk image (includes documentation) hdapm.dmg
Source code hdapm-source.tar.gz