smanual power off Harddisk?

[zimu]

I know there's a power save option to power down your HDD after 3 mins.

however i'm wondering if there's some program where you can manually turn off the harddisk? the 3 mins thing doesn't seem to work for me. i knwo there has to be something, i just got a program that can adjust my fan speed (i have a laptop) according to my temperature specifications, so much easier that way and quieter!!

thanks