How to check if internal HDD spindle is off after unmount I use SSD instead of optical drive in my Macbook MC516LL, so I have bunch of reasons why I wants to keep HDD's spindle off:


Preserve HDD from shock
Reduce energy consuming
Reduce overall system temperature


I use diskutil umount HD250 and it disappears from OSx.
So how can I  check if spindle turned off?

Thanks!
diskutil umount HD250 - doesn't turn off spindle

diskutil eject HD250 - turn off spindle

confirmd by sound and mA usage