Dell PERC13 and PERC12 User’s Guide PERC H975 Series and PERC H965 Series cards

Physical disk power management is a power-saving feature of PERC12 series cards. The feature allows disks to be spun down based on disk configuration and I/O activity. The feature is supported on all rotating SAS and SATA disks, and includes unconfigured and hot-spare disks. By default, the physical disk power management feature is enabled on unconfigured drives and disabled on hot-spare drives.