IBM 306m - eServer xSeries - 8849, Problem Determination And Service Manual

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Memory problems
v Follow the suggested actions in the order in which they are listed in the Action column until the problem
is solved.
v
See Chapter 3, “Parts listing, Type 8849 and Type 8491 server,” on page 19 to determine which
components are customer replaceable units (CRU) and which components are field replaceable units
(FRU).
v
If an action step is preceded by “(Trained service technician only),” that step must be performed only by a
trained service technician.
Symptom Action
The amount of system memory
that is displayed is less than the
amount of installed physical
memory.
1. Make sure that:
v No error LEDs are lit on the operator information panel.
v Memory mirroring does not account for the discrepancy.
v The memory modules are seated correctly.
v You have installed the correct type of memory.
v If you changed the memory, you updated the memory configuration in the
Configuration/Setup Utility program.
v
All banks of memory are enabled.
v
The server did not automatically disabled a memory bank when it detected a
problem.
v
A DIMM was not disabled by POST with an error LED light on.
2. Check the POST error log for error message 289. If a DIMM was disabled by a
system-management interrupt (SMI), replace the DIMM.
3. Run memory diagnostics (see “Running the diagnostic programs” on page 89).
4. Add one pair of DIMMs at a time, making sure that the DIMMs in each pair are
matching.
5. Reseat the DIMMs.
6. Replace the following components one at a time, in the order shown, restarting
the server each time:
a. DIMMs
b. (Trained service technician only) System board
Microprocessor problems
v Follow the suggested actions in the order in which they are listed in the Action column until the problem
is solved.
v
See Chapter 3, “Parts listing, Type 8849 and Type 8491 server,” on page 19 to determine which
components are customer replaceable units (CRU) and which components are field replaceable units
(FRU).
v
If an action step is preceded by “(Trained service technician only),” that step must be performed only by a
trained service technician.
Symptom Action
The server emits a continuous
beep during POST, indicating
that the startup (boot)
microprocessor is not working
correctly.
1. Correct any errors that are indicated by the LEDs (see “System board LEDs”
on page 87).
2. Make sure that the server supports the microprocessor.
3. (Trained service technician only) Make sure that the microprocessor is seated
correctly.
4. (Trained service technician only) Replace the microprocessor.
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IBM xSeries 306m Types 8849 and 8491: Problem Determination and Service Guide