Put a hd to sleep
 

I have to hd's on my computer and one of them is very noisy, i want to put it to sleep (shut it down) when i'm not using it.
How do i do? I use Slackware 9 if you need to know.

Live with it or get a new one. You don't want to power down hard drives because it decreases its lifetime everytime you shut it down.

If you must, you can use hdparm. I think echoing an address to the hard drive might work too.