There's a myth that says your computer uses more power to power down and start up again than just leaving it on when not using it. But if you want to save on energy being used by your computer, the answer is very simple: switch it off when you're not using it.

However, most people don't like switching off their computers when not in use, because it means having to sit through a lengthy start-up process as your computer reloads its operating system.

Personally, I don't mind waiting, but if you do, then there are some easy tweaks that you can implement.

In Windows XP:

1. Click on "Start" and then on "Control Panel". A new window pops up.
2. If you're in Classic View: click on "Power Options". If you're in Category View: click on "Performance and Maintenance" and then on "Power Options". A new window pops up.
3. On the "Power Schemes" tab, click on the drop-down menus next to "Turn off monitor", "Turn of hard disks" and "System standby" and select time options that will suit your need. I suggest you stagger the times so that they don't all happen at the same time (start with the monitor, then your hard disk, and then followed by system standby).
4. On the "Hibernate" tab, click the button next to "Enable hibernation".
5. Click on "OK".

In Windows Vista:

1. Click on "Start" and then on "Control Panel". A new window pops up.
2. If you're in Classic View: click on "Power Options".
   If you're in Control Panel Home view: click on "Performance and Maintenance" and then on "Power Options". A new window pops up.
3. On the left, click on "Choose when to turn off the display". A new window opens.
4. Click on the drop-down menus next to "Turn off the display" and "Put the computer to sleep" and choose the times you prefer. I suggest you stagger the times so that they don't all happen at the same time (start with the monitor and then followed by sleep).
5. Now click on "Change advanced power settings". A new window pops up.
6. Click on the "+" sign next to "Sleep". Now click on the "+" sign next to "Hibernate after". Specify a time (if it currently reads "Never", click on it and then specify a time).
7. Click on "OK".
8. Click on "Save changes".

The difference between System standby (or sleep mode for Vista) and Hibernation is that with the former option, only a few of your components are switched off (saving power), while in the latter everything will shut off (saving the most power).

Hibernation does, however, save all your current open programs so when you switch it on again, your computer doesn't need to go through the entire start-up process again, but will simply load your system as it was before it went into hibernation.

Got any further tips? Then please leave a comment below.