IBM pSeries 670, Service Manual

Page: 839 / 1032

L3 Cache Modules
Handling Static-Sensitive Modules
Attention: MCM and L3 modules are sensitive to static electricity discharge. These devices are shipped
in antistatic containers to prevent damage caused by electrostatic discharge.
Take the following precautions:
v Use an antistatic wrist strap while handling the device.
v
Do not remove the device from the antistatic container until you are ready to install the device in the
system unit.
v With the device still in its antistatic container, touch it to a metal frame of the system.
v
Grasp modules by the heatsink. Avoid touching the interposer buttons.
v If you need to lay the device down while it is out of the antistatic container:
– Lay the MCMs with the posts down on the antistatic mat.
– Lay the L3s with the LGA connector down in the antistatic tray.
Before picking it up again, touch the antistatic container and the metal frame of the system unit at the
same time.
v Handle the devices carefully in order to prevent permanent damage.
Attention: Before you remove or replace any L3 cache module, stop , read and understand this entire
procedure. Also, check to ensure that the MCM/L3 Label Map is installed, refer to “Installing the
MCM/L3/Passthrough Plug Map” on page 791.
Attention: The L3 cache modules in this system can be attached to the backplane a maximum of three
times. If an L3 cache module is removed for a fourth time, it must be replaced with a new L3 cache
module. Check the
MCM/L3 Label Map to determine how many times the module has been removed
before. New L3 cache modules are shipped with a new MCM/L3 plug count adhesive replacement label.
When you install a new L3 cache module, place the new label in the correct position on the
MCM/L3 Label
Map . If a new MCM/L3 Label Map is needed, see “Tools” on page 962 for replacement label part number.
Removal
Attention: If more than one module is to be replaced or reseated, begin with the uppermost module,
replace it and then go to the next highest position module, until the lowermost module has been replaced
or reseated.
1. Turn off power as described in “Powering Off and Powering On the System” on page 779.
2. Remove the fan chassis. See “Fan Chassis” on page 849.
3. Perform a general cleaning operation using a sash brush, ( not the one included with the FRU kit) and
vacuum cleaner (see “Tools” on page 962 for tool part numbers) to remove any accumulated dust and
debris that has settled in the processor subsystem. Hold the vacuum hose near the brush to remove
any debris the brush generates.
4. Note the location of the module being removed.
Note: Arrange the four 4-position trays on the ESD mat in a pattern that corresponds to the locations
of the L3 cache modules on the system backplane.
Attention: Each L3 cache module must be returned to the location from which it was removed.
Check the MCM/L3 Label Map on the system to confirm the number of times the target module has
been unplugged. If it has been unplugged three times, order a new module. If this is the first
removal/reseat for the module, record the serial number of the module and the date of the action.
Chapter 9. Removal and Replacement Procedures
819