IBM CS821 Service Manual page 57

Before you begin
Before you begin replacing the system backplane, record the system serial number and machine model
type. After you replace the system backplane, you must set the system serial number and machine model
type in the system backplane.
Power off the system and place it in the service position. For instructions, see "Preparing the 8001-12C or
8005-12N system to remove and replace internal parts" on page 70.
About this task
You can use a commercially available magnetic tip screwdriver to remove and replace the screws.
As part of the system backplane replacement, the system processor modules are moved from the old
system backplane to the new system backplane.
As part of the system processor module replacement, the heat sink is removed. When the heat sink is
removed from the system processor module, the thermal interface material (TIM) is typically adhered to
the heat sink. Unless damaged, the TIM that is adhered to the heat sink can be reused. If the TIM is
damaged, do not reuse the removed heat sink. Before you begin the processor removal and replacement
procedure, ensure that you have a spare TIM and heat sink on hand.
Procedure
1. Attach the electrostatic discharge (ESD) wrist strap.
Attention:
v Attach an electrostatic discharge (ESD) wrist strap to the front ESD jack, to the rear ESD jack, or to
an unpainted metal surface of your hardware to prevent the electrostatic discharge from damaging
your hardware.
v When you use an ESD wrist strap, follow all electrical safety procedures. An ESD wrist strap is
used for static control. It does not increase or decrease your risk of receiving electric shock when
using or working on electrical equipment.
v If you do not have an ESD wrist strap, just prior to removing the product from ESD packaging
and installing or replacing hardware, touch an unpainted metal surface of the system for a
minimum of 5 seconds.
2. Remove both power supplies from the system. For instructions, see "Removing a power supply from
the 8001-12C, 8001-22C, 8005-12N, or 8005-22N" on page 78.
3. Remove the processor air baffle as shown in Figure 46 on page 42. Carefully unsnap and lift the
processor air baffle from the system.
Removing and replacing parts
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