Q: I have heard that turning the computer on and off during the day is not good for the hard drives, but I am worried about saving energy.
A: It take about I think like 10 (so I've heard) hours of on time to complete the energy that it takes to boot, I may be way off on that, especially with newer computer, however, it still remains true that the energy to turn it on, is way more then to leave in on for an hour, also, this can ruin the hard drive. Sleep mode isn't much better, for an hour, just turn off the monitor and be done with it.