IBM pSeries 690 Service Manual page 902

Replacement or New Installation
Note: This procedure is to be performed only by trained service personnel.
1. Go to "Methods for Testing MCMs and Pass Through Modules for a Short Circuit" on page 888 and
install the MCM/L3 module short-circuit test tool. Use the test tool during the MCM replacement
procedure to ensure that the MCMs are installed without a short circuit. If you install an MCM and
encounter a short circuit, the MCM you installed must be replaced.
2. If installing a new MCM, insert the new actuation bolt supplied with the new MCM module and move
the actuation bolt and spring assembly to the up position and hand-tighten to hold the assembly in
the up position. Perform a general cleaning operation, using a sash brush, (not the one included with
the FRU kit) and vacuum cleaner (see "Tools" on page 1051 for the 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.
3. Loosen the captive bolt in the center of the protective cover and remove the cover from the new
MCM module, as shown in the following illustration.
4. If you are installing MCMs with the aluminum heatsink, go to substep 5. If you are installing MCMs
with the copper heatsink, do the following:
Note: The field restocking plan, is to replace the 1.7 GHz copper heatsink MCM (factory installed)
with a 1.7 GHz aluminum heatsink MCM.
a. Ensure that the stiffener located on the backplane is aluminum and not plastic.
b. Insert the two steel alignment rods into the aluminum backplane stiffener.
c. Ensure that the locking cams located on the aluminum backplane stiffener are in the open position
d. Grasp the module across the narrow span of the heatsink cap. Align the corner chamfer (flat
corner) on the MCM module or the pass through to match the outline on the backplane.
e. Align the two steel alignment rods with the clearance holes located on each side of the MCM.
f. Insert the MCM clearance holes over the two steel alignment rods and slide the MCM module into
the socket, and maintain pressure while closing both locking cams.
g. Use an 5-mm locking socket wrench to secure the locking cams over the MCM.
h. Go to substep 6.
5. Grasp the module across the narrow span of the heatsink cap. Align the corner chamfer (flat corner)
on the MCM module or the pass through to match the outline on the backplane.
Attention: Verify that the guide pins protrude above the connectors.
Carefully push the MCM module into the socket. If your system has the plastic backplane stiffener,
use an 8-mm locking socket wrench to secure the locking cams over the MCM. Be sure to maintain
pressure on the MCM when securing both locking cams.
6. Loosen the actuation bolt at the rear of the MCM module.
7. Push the actuation bolt in and slide the spring plate assembly to the down position.
886 Eserver pSeries 690 Service Guide