IBM eserver xSeries 232 8668 Hardware Maintenance Manual page 71

2. Obtain an SMP-capable operating system (optional). For a list of supported
operating systems, see http://www.ibm.com/pc/us/compat/ on the World
Wide Web.
3.
Your server comes with one microprocessor installed in the microprocessor
connector (U68) that is closest to the power supply. This is the startup (boot)
microprocessor. A microprocessor installed in connector U69 is microprocessor
2. If more than one microprocessor is installed, the microprocessor installed in
microprocessor connector U69 is the startup processor, and the microprocessor
installed in U68 is the application processor.
Attention: To avoid damage and ensure proper server operation when you install
a new or additional microprocessor, use microprocessors that have the same cache
size and type, and the same clock speed. See the ServerProven list at
http://www.ibm.com/pc/compat for a list of microprocessors for use with your
server.
Installing a microprocessor
Installing options
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