Service manual

Chapter 6 Replacing Parts
70
Warnings and Cautions
These warnings and cautions apply whenever you remove covers of the system. Only a technically qualified
person should integrate, configure, or service the system.
WARNING System power on/off: The on/off button (a convex button) on the front of the
chassis DOES NOT turn off the system AC power. To remove power from system,
you must unplug the AC power cord from the wall outlets or the system.
Hazardous conditions, power supply: Hazardous voltage, current, and energy
levels are present inside the power supply. There are no user-serviceable parts
inside it; servicing should be done by technically qualified personnel.
Hazardous conditions, devices, and cables: Hazardous electrical conditions may
be present on power, telephone, and communication cables. Turn off the system
and disconnect the power cords, telecommunications systems, networks, and
modems attached to the system before opening it. Otherwise, personal injury or
equipment damage can result.
Hazardous conditions, processors and power pods: Thermal conditions may be
present in the processor/memory complex. Allow all fans to continue to run until they
shut down on their own after power has been turned off. After the fans stop, the
power cords can be removed.
CAUTION Electrostatic discharge (ESD) and ESD protection: ESD can damage disk
drives, boards, and other parts. We recommend that you do all procedures in this
chapter only at an ESD-protected workstation. If one is not available, provide some
ESD protection by wearing an antistatic wrist strap attached to chassis groundany
unpainted metal surface on your system when handling parts.
ESD and handling boards: Always handle boards carefully. They can be
extremely sensitive to ESD. Hold boards only by their edges. After removing a
board from its protective wrapper or from the system, place it component-side UP on
a grounded, static-free surface. If you place the I/O carrier on a conductive surface,
the battery leads may short out. If they do, this will result in a loss of CMOS data
and will drain the battery. Use a conductive foam pad if available but NOT the board
wrapper. Do not slide board over any surface.
Cooling and airflow: For proper cooling and airflow, always install the chassis
covers before turning on the system. Operating the system without the covers in
place can damage system parts.