"A Lawrence Berkely Lab study in 1999 approximated that one computer and monitor left on overnight is responsible for powerplants emitting nearly one ton of carbon dioxide per year. If every computer and monitor in the US were shut off overnight, 8 large powers stations could be shut down and 7 million fewer tons of carbon dioxide would be emitted."

There are also guidelines from the US Dept. of Energy about when to turn your computer off or leave it on at http://www.eere.energy.gov/consumer/.../mytopic=10070

The gist is, turn off your monitor if you aren't going to use your PC for more than 20 minutes, and turn off both the CPU and monitor if you're not going to use your PC for more than 2 hours.

It's left on except in a bad thunderstorm.

We shut ours down every night and turn them on in the morning.

Never thought if its good or bad...I always leave it on,and I use it first thing in the morning while still in bed to check emails and such

I put my work computer into standby every night.. and turn it off on Fridays. But my laptop at home is always on.. I dont even know what power settings it has.. I'm going to take a look.

We have a Mac and it gets put to sleep whenever it's not in use.

With as quickly as computers become obsolete I don't think turing it off at night is really going to wear it out before it'd need replacement anyway. Anyway, computers only have a 3 year life span regardless.

As you've discovered, antivirus programs do nothing to prevent hacking. For that you need a firewall. Antivirus only protects against viruses you may get via email or disc. Hackers come in through an open port that a firewall can close and prevent access to.

Yeah, for most of the world, that is the case. However, there are many general users that do not upgrade. My grandfather still uses an 8+ yo hand-me-down PC. We keep it running for him so he can play his games. We just upgraded the RAM and HD once. And with that 8 years also comes a longer bootup. LOL Which is another reason I don't personally shut mine down. When I need it, I need it. I don't have time to wait for Bill Gates to have his morning coffee and load Windows for me.

I turn the monitor off but not the computer.

I turn mine off every time I get out of my room for a long period of time. I dont think there is any need for my to have it on if I'm not using it.

My home computer is always turned off as soon as I am finished with whatever I am doing. I am trying my best to leave the smallest ecological footprint, and this is a part of it. No matter how little energy it takes on standby, it still takes energy. For the same reason, I never leave my coffee maker plugged in - it has the time display and that takes energy, too.
I always turn off the light when leaving the room, so typically, in my house the light is on only in one room at at time.
I recycle as much as I can and I compost all compostable food scraps. Typically, I put out one bag of garbage every other week. I cringe when I see people having 6 bursting garbage bags at the curb every single week.

we just put our pc to sleep by hibernation if you hit crtl+alt+delete you can choose to put it to sleep and you wont lose any data or anything.

how do you put a laptop into sleep mode? Is it automatic or something you need to do with the setup?

We turn ours off if we're not going to be using them for a while. Generally at night. I'm leery of hackers and it's a big energy drain. We used to leave them on all the time and since we've stopped, we've noticed a difference in our energy bill.

It should be in your "system preferences" (or equivalent, based on your OS). You just tweak the settings to put the monitor to sleep when inactive for X amount of time, hard drive to sleep when inactive for Y amount of time, OR you can choose to use the pre-set "better performance" or "energy saver" settings. You can also have one setting for when you're using the battery and another for when you're using the power adapter.

HTH,

Right click your desktop. In the Display Properties dialog box, click the Screen Saver tab and click the Power button. You can change your settings there to power down your monitor or hard disks.