IBM 8685 - eServer xSeries 255, Installation Manual

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Installing an additional microprocessor
Your server comes with one microprocessor installed in microprocessor socket 1
(labeled CPU1) on the system board. The microprocessor in socket 1 is the startup
(boot) microprocessor. If more than one microprocessor is installed, the
microprocessor installed in the highest-numbered socket is the microprocessor from
which the server will start. Therefore, the microprocessors installed in the
lowest-numbered sockets are used as application microprocessors.
Attention: To avoid damage and ensure proper server operation when you install
an additional microprocessor, use microprocessors that have the same cache size
and type, and the same clock speed. Microprocessor internal and external clock
frequencies must be identical.
Before you install microprocessors, review the following:
v To order additional microprocessor options, contact your IBM reseller or IBM
marketing representative.
v When you install an additional microprocessor, you must also install the voltage
regulator module (VRM) that comes with the microprocessor in the corresponding
VRM connector.
A VRM metal retaining-clip housing comes installed in the empty microprocessor
VRM connectors for microprocessors 3 and 4. When you install a VRM in
connector 3 or 4, you must first remove the VRM metal retaining-clip housing
from the appropriate VRM connector. You must also remove the metal retaining
clip from the VRM metal retaining-clip housing when installing a VRM.
v The microprocessor speed is automatically set for your server; therefore, you do
not have to set any microprocessor-speed jumpers or switches. For a list of
supported microprocessor speeds, go to http://www.ibm.com/eserver/ on the
World Wide Web.
v The microprocessor sockets in this server contain built-in termination for the
microprocessor bus; therefore, terminator cards are not required for empty
microprocessor sockets. However, each empty microprocessor socket contains a
protective, flat plastic cover that you must remove before you install a
microprocessor in these sockets.
v
To ensure proper server operation, microprocessor socket 4 contains a plastic
microprocessor baffle that resembles a heat sink. You must remove the
microprocessor baffle when you install a microprocessor in socket 4. Otherwise,
the microprocessor baffle must remain in place to ensure proper airflow in your
server.
When you install additional microprocessors and VRMs, install them in the order
listed in Table 3. The corresponding VRM connector is located adjacent to the
microprocessor socket.
Important: If you do not install the microprocessors in the correct order, the server
will not operate properly.
Table 3. Microprocessor and VRM installation order
Microprocessor number Microprocessor socket
label VRM connector
1 (standard) CPU1 J34 (standard, plastic
retaining clip provided on
VRM housing)
Chapter 2. Installing options
17