Dell OptiPlex DHM, Setup And Quick Reference Manual

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S e t u p a n d Q u i c k Re f e r e n c e G u i d e
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NOTICE:
To help avoid damaging a computer with a manual voltage selection switch, set the
switch for the voltage that most closely matches the AC power available in your location. For Japan,
the voltage selection switch must be set to the 115-V position even though the AC power available in
Japan is 100 V. Also, ensure that your monitor and attached devices are electrically rated to
operate with the AC power available in your location.
• Before working inside the computer, unplug the computer to help prevent electric shock
or system board damage. Certain system board components continue to receive power
any time the computer is connected to AC power.
When Working Inside Your Computer
Before you open the computer cover, perform the following steps in the sequence indicated.
CAUTION: Do not attempt to service the computer yourself, except as explained in
your online Dell documentation or in instructions otherwise provided to you by Dell.
Always follow installation and service instructions closely.
NOTICE: To help avoid possible damage to the system board, wait 5 seconds after turning off the
computer before removing a component from the system board or disconnecting a device from the
computer.
1
Perform an orderly computer shutdown using the operating system menu.
2
Turn off your computer and any devices connected to the computer.
3
Ground yourself by touching an unpainted metal surface on the chassis, such as the metal
around the card-slot openings at the back of the computer, before touching anything
inside your computer.
While you work, periodically touch an unpainted metal surface on the computer chassis
to dissipate any static electricity that might harm internal components.
4
Disconnect your computer and devices, including the monitor, from their electrical
outlets. Also, disconnect any telephone or telecommunication lines from the computer.
Doing so reduces the potential for personal injury or shock.
When Using Your Computer (continued)