You shouldn't have to turn it off because atleast on Windows 7 - by default it will go to sleep after certain inactivity. And then wake up after a few hours and

You shouldn't have to turn it off because atleast on Windows 7 - by default it will go to sleep after certain inactivity. And then wake up after a few hours and go to hibernate. Since hibernate is 0 power state, it is as good as turn off. Additionally, you don't lose any of your in-memory data.