3.Disconnect all network cables from the computer.
4.Disconnect your computer and all attached devices from their electrical outlets.
5.Press and hold the power button while the computer is unplugged to ground the system board.
6.Remove the cover.
CAUTION: Before touching anything inside your computer, ground yourself by touching an unpainted metal surface, such as the metal at the back of the computer. While you work, periodically touch an unpainted metal surface to dissipate static electricity, which could harm internal components.
Turning Off Your Computer
CAUTION: To avoid losing data, save and close all open files and exit all open programs before you turn off your computer.
1.Shut down the operating system:
–In Windows 8:
*Using a
a.Swipe in from the right edge of the screen, opening the Charms menu and select Settings.
b.Select the 
and then select Shut down
*Using a mouse:
a.Point to
b.Click the 
and select Shut down.
–In Windows 7:
1.Click Start
.
2.Click Shut Down.
or
1.Click Start
.
2.Click the arrow in the 
2.Ensure that the computer and all attached devices are turned off. If your computer and attached devices did not automatically turn off when you shut down your operating system, press and hold the power button for about 6 seconds to turn them off.
After Working Inside Your Computer
After you complete any replacement procedure, ensure you connect any external devices, cards, and cables before turning on your computer.
1.Replace the cover.
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