I have a full sized HDD in a USB 3 dock, and my power settings inactive timer is set to 300 minutes. This doesn’t appear to be applying to the docked HDD, as it spins down in about 5 minutes or less. It takes forever to spin back up when I access it, so how can I change this?
Two things you can try is disabling USB selective suspend. The same section of power options has an option for Turn off hard disks after…
So the “turn off disks after” setting was already set, and USB selective suspend already disabled, BUT those are apparently overridden for USB connected drives if the “Allow the computer to turn off this device” box is checked for that USB hub in Windows Device Manager (Power Management tab).
All of those had defaulted to ‘on’ since I upgraded my mobo, so I think I’ve got it now.