Hibernation is a clever trick designed to save battery life on notebook computers but it is also useful for desktops as well.

When a computer hibernates, all the information in its memory is saved on a large file on the hard disk and the computer powers down. For a notebook this saves battery life, but for a desktop computer it reduces the amount of time needed to start up and shut down. You will need to do a proper restart every so often to maintain performance.

The options for hibernation can be found in the Control Panel. Left-click on the Start button and then on Control Panel. Click on the Performance and Maintenance icon in the category view and then on Power Options. If you are using Classic view, double-click on the Power Options icon.

Left-click on the Hibernate tab on the right of the screen and then in the box labelled 'Enable Hibernation'. Also make sure that there is enough disk space to hibernate; Windows needs as much hard disk space as there is memory in the computer. Click on Apply to save the changes.

It's also worth changing Windows to hibernate when the power button is pressed. Click on the Advanced tab and look for the 'When I press the power button on my computer' option. Click on the down arrow and select Hibernate. Click on Apply again and then on OK.

There are two different shutdown menus in Windows, one uses a dropdown menu and the other shows icons with the various shutdown options.

Most copies of Windows XP Home use the icons. Left-click on the Start button and then on Turn off computer. Don't worry that the Hibernate icon isn't showing, press the Shift key and the Stand By option will change to Hibernate. Don't let go of the Shift key and left-click on the Hibernate icon. To turn the computer back on press the power button as normal.

For Windows with the dropdown menu, left-click on the down arrow and then on Hibernate. Windows should remember the last option you chose so this will be available the next time you click on Turn off Computer.