Seagate ST91000642SS Constellation SATA Product Manual - Page 20

3.8.4 Power-management modes PowerChoiceTM power management Drives using the load/unload architecture provide programmable power management to tailor systems for performance and greater energy efficiency. The table below lists the supported PowerChoice modes. The further you go down in the table, the more power savings you get. For example, Idle_B mode results in greater power savings than Idle_A mode. Standby mode results in the greatest power savings. Mode Idle_A Idle_B Idle_C Standby Description Reduced electronics Heads unloaded. Disks spinning at full RPM Heads unloaded. Disks spinning at reduced RPM Heads unloaded. Motor stopped (disks not spinning) PowerChoice can be invoked using one of these two methods: • Extended Power Conditions (EPC) Set Features Command method-Enable and initialize the idle condition timers. • Standby Immediate and Idle Immediate command method-Use the EPC Set Features Command. This allows the host to directly transition the drive to any supported PowerChoice mode. The drive preserves the existing idle power settings. PowerChoice reporting methods PowerChoiceTM provides these reporting methods for tracking purposes: Check Power Mode Reports • Current power condition Power Condition Log Reports • Idle condition enabled/disabled • If timer is changeable • Typical recovery time from extended power conditions • Current timer setting and Manufacturer default timer settings SMART Read Data Attribute - Load/ Unload Cycle Counter 14 Constellation Serial ATA Product Manual, Rev. D