IBM eserver xSeries 350, User Reference Manual

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IBM® xSeries 350: User’s Reference
5. If you replace the microprocessors in your server with microprocessors of a
different speed, set the microprocessor-core-frequency-selection jumper block as
described in Table 5. To ensure that your server maintains the correct
microprocessor bus-to-core ratio, you must set the microprocessor speed (core-
frequency-selection) in the following order, from front to back: J13, J27, J28, and
J29.
Note: See “Changing jumper positions” for additional information on setting
jumpers.
6. If you have other options to install or remove, do so now; otherwise, go to
“Installing the server top cover and bezel” on page 62.
Changing jumper positions
Jumpers on the system board help you to customize the way your server operates.
Your server system board contains three-pin jumper blocks. In some cases, jumper
settings might be combined to define a function.
On a three-pin jumper block, each jumper covers two of the three pins. You can
position the jumper to fit over the center pin and either of the other two pins. To
Table 5. Microprocessor-core-frequency-selection jumper block settings.
Bus Ratio
Core Frequency
(MHz)
J13 J27 J28 J29
Pins 2 and 3 Pins 1 and 2 Pins 2 and 3 Pins 1 and 2 7:1 700/100
Pins 1 and 2 Pins 2 and 3 Pins 2 and 3 Pins 1 and 2 8:1 800/100
Microprocessor
speed jumpers
J13
J27
J28
J29
1 2 3