I'm putting together a new server and was about to order four 2-terabyte
Western Digital "Green" enterprise hard drives for it.

I've never really thought about why these drives are called "green,"
other than they are supposed to use less power than "non-green" drives.
Obviously, they do this by shutting the drive down when it isn't being
accessed.

Apparently, though, when you use "green" drives in a server, you end up
with a dramatically high Load/UnLoad Cycle Count, and this can lead to
premature ejac-, er, drive failure.

There is a way to turn off the "green" on the WD drives, by adjusting
the drive's idle timer to lower the Load/Unload cycle rate, but it is a
pain in the ass, involving preparing a DOS boot disk, installing the
drive in a computer, and running a program. Not difficult, but I don't
have a "Windoze" computer anymore that can boot up into DOS. :)

I'm guessing the "green" drives of other vendors will behave similarly.

Sheesh, I never learned any of this stuff in my college English classes.
Even an O.F. like me is not too old to learn.