Use less electricity by configuring the power options.
There are several settings for even power users who prefer to leave computers on all the time.
Click Start, Settings and click Control Panel.
In the Control Panel window, click the link on the left - Classic View.
If you're already in Classic View, leave it there.
Open Power Options.
In the Power Options dialog box, click on the Power Schemes tab.
On your desktop computer, you'll probably see the Power schemes setting set to Home/Office Desk.
In the Settings for Home/Office power scheme frame, click the down arrow on the Turn off monitor drop down list box.
I set this to 10 minutes. It will put the monitor on stand-by and cut the power used.
To reactivate the screen, move the mouse and the monitor will start automatically.
Set Turn off hard disks to about 30 minutes.
The disks will spin down and save power.
If your disk is powered down there will be a delay while they spin up.
You can also try System Standby settings, but if you have USB or Firewall devices on your machine, it may not work right and cause problems.
Click Apply and then click OK
Take time and test the best delay setting for your disk(s) and monitor.