Removing the System Board: Mini Tower, Desktop, and Small Form Factor Computers
Shut down the computer through the Start menu.
Ensure that your computer and attached devices are turned off. If your computer and
attached devices did not automatically turn off when you shut down your computer, turn
them off now.
NOTICE: To disconnect a network cable, first unplug the cable from your computer and then unplug it from the network wall jack.
Disconnect any telephone or telecommunication lines from the computer.
Disconnect your computer and all attached devices from their electrical outlets, and then
press the power button to ground the system board.
CAUTION: To guard against the electrical shock, always unplug your computer from the electrical outlet before removing the cover.
NOTICE: 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 any static electricity that could harm internal components.
Remove any components that restrict access to the system board (CD/DVD drive(s), floppy
drive, hard drive, I/O panel (except for small form factor computer).