The man page referenced in this answer indicates that hdparm -S sets the spin-down time, while -B sets the APM level, and also suggests that -B is a hardware thing (implying -S is software?) However, ...
I want to make two drives sleep after 15 minutes of idle (sdb and sdc) on Linux Arch. I have the idea that hdparm should be able to help me. I can put the disks into standby (hard disk spins down, ...
What do different values of hard drive's Advanced Power Management feature (hdparm -B) affect, except spin-down?
hdparm's -B parameter is documented as: Get/set Advanced Power Management feature, if the drive supports it. A low value means aggressive power management and a high value means better per‐ ...