Advanced Power Management (APM)

The advanced power management appeared as an option in the hard disk drives supporting ATA/ATAPI-4 or higher standard. Change of its value from 1 to 254 allows regulating the performance of the HDD and, thereby, to save energy of power supplies. Value less than 128 enables the hard drive to stop the spindle motor without any commands during given period time, which allows saving as much energy of the power supply as possible, but leads to the increased deterioration of kinematics and the delay at the waking caused by waiting of magnetic disks spinning up to the necessary speed. The work of the advanced power management implemented in the storage devices does not depend on the "sleep" timer of the operating system.