To manually put your computer on standby
Open Power Options in Control Panel.
On the Advanced tab, under When I press the power button on my computer, click Standby. If you are using a portable computer, click Standby under When I close the lid of my portable computer.
Click OK or Apply, and then turn off the power or close the lid of your portable computer.
To open Power Options, click Start, click Control Panel, click Performance and Maintenance, and then click Power Options.
You can also put your computer on standby by clicking Start and then clicking Shut Down. In the What do you want the computer to do drop-down list, click Stand by.
You might want to save your work before putting your computer on standby. While the computer is on standby, information in computer memory is not saved on your hard disk. If there is an interruption in power, information in memory is lost.
To put your computer on standby, you must have a computer that is set up by the manufacturer to support this option.
Using Power Options in Control Panel, you can adjust any power management option that your computer's unique hardware configuration supports. Because these options may vary widely from computer to computer, the options described may differ from what you see. Power Options automatically detects what is available on your computer and shows you only the options that you can control.