Just like Windows XP, Windows Vista can use hibernation to save battery life. Power is handled differently in Windows Vista.

Microsoft tells us that its new operating system does not need to shut down as often as Windows XP so it goes into Sleep mode instead.

The hard disk and graphic card shut down but the system memory is still active and drawing power. If you're a notebook user this is a bad thing, because it still draws power and can be a problem if the is cut off suddenly.

Hibernation uses even less power and keeps files safe, so it is better for a desktop computer that is turned off at the wall.

The hibernation options can be found in Control Panel. Left-click on the Start button and then on Control Panel. Click on the Mobile PC icon in the bottom left and then on Power Options. This displays the different power plans on the computer with some little graphs to explain their benefits.

We're currently using the Power Saver plan, so click on the 'Change plan settings' link. and then on 'Change advanced settings'. Click on the small plus button next to the Sleep option and then on the one next to 'Hibernate after'. Change the settings to 15 minutes on battery and 30 minutes on Power.

It's also worth enabling hybrid sleep. This is a new version of sleep that saves important files to the hard disk in case the power is removed.

To change how Vista acts when you press the power button, click on the plus next to 'Power buttons and lid' and then on 'Start menu power button'. Select Hibernate from the menu. There are separate options for when on battery or mains power. You can also set this for the physical power button.

When you are happy with the changes click on the OK button to save the changes and then on Cancel to return to the Select a Power plan window. If you use more than one plan, it is a good idea to repeat these instructions with the other plans. Close this window.

To hibernate, click on the Start button and then on the power icon. If you hover the mouse over it you will notice that the tool tip has changed to describe hibernation.

To use the other options such as logging off or sleep, click on the arrow to the right of the power button and select the option you want from the menu that appears.

Click here for our guide to enabling hibernation in Windows XP.