Before Working Inside Your Computer - Dell OptiPlex 755 Quick Reference Manual

NOTICE:
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 4 seconds to turn
them off.

Before Working Inside Your Computer

Use the following safety guidelines to help protect your computer from
potential damage and to help ensure your own personal safety.
CAUTION:
safety instructions in the Product Information Guide.
CAUTION:
or contacts on a card. Hold a card by its edges or by its metal mounting bracket.
Hold a component such as a processor by its edges, not by its pins.
NOTICE:
Only a certified service technician should perform repairs on your
computer. Damage due to servicing that is not authorized by Dell is not covered by
your warranty.
NOTICE:
When you disconnect a cable, pull on its connector or on its strain-relief
loop, not on the cable itself. Some cables have a connector with locking tabs; if you
are disconnecting this type of cable, press in on the locking tabs before you
disconnect the cable. As you pull connectors apart, keep them evenly aligned to
avoid bending any connector pins. Also, before you connect a cable, ensure that
both connectors are correctly oriented and aligned.
NOTICE:
To avoid damaging the computer, perform the following steps before you
begin working inside the computer.
1 Turn off your computer.
2 If the computer is connected to a docking device (docked), undock it. See
the documentation that came with your docking device for instructions.
NOTICE:
To disconnect a network cable, first unplug the cable from your computer
and then unplug it from the network wall jack.
3 Disconnect all telephone or network cables from the computer.
4 Disconnect your computer and all attached devices from their electrical
outlets, and then press the power button to ground the system board.
5 If applicable, remove the computer stand (for instructions, see the
documentation that came with the stand) and the cable cover, if attached
(see "Cable Cover (Optional)" on page 57).
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Quick Reference Guide
Before you begin any of the procedures in this section, follow the
Handle components and cards with care. Do not touch the components