Microprocessor Problems - Lenovo NeXtScale nx360 M5 Installation And Service Manual

Table 9. Memory problems and actions
Symptom
The amount of system memory
that is displayed is less than
the amount of installed
physical memory.
Multiple rows of DIMMs in a
branch are identified as failing.

Microprocessor problems

• Follow the suggested actions in the order in which they are listed in the Action column until the problem is
solved.
• If an action step is preceded by '(Trained technician only)', that step must be performed only by a Trained
technician.
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Action
Note: Each time you install or remove a DIMM, you must disconnect the server from
the power source; then, wait 10 seconds before restarting the server.
1. Make sure that:
• No error LEDs are lit on the operator information panel.
• No DIMM error LEDs are lit on the system board.
• The memory modules are seated correctly.
• You have installed the correct type of memory.
• If you changed the memory, you updated the memory configuration in the
Setup utility.
• All banks of memory are enabled. The server might have automatically
disabled a memory bank when it detected a problem, or a memory bank
might have been manually disabled.
• There is no memory mismatch when the server is at the minimum memory
configuration.
2. Reseat the DIMMs, and then restart the server.
3. Check the POST error log:
• If a DIMM was disabled by a systems-management interrupt (SMI), replace
the DIMM.
• If a DIMM was disabled by the user or by POST, reseat the DIMM; then, run
the Setup utility and enable the DIMM.
4. Check that all DIMMs are initialized in the Setup utility; then, run memory
diagnostics (see "Running DSA Preboot diagnostic programs" on page 65).
5. Make sure that there is no memory mismatch when the server is at the minimum
memory configuration.
6. Add one pair of DIMMs at a time, making sure that the DIMMs in each pair
match.
7. Reseat the DIMM.
8. Re-enable all DIMMs using the Setup utility, and then restart the server.
9. Replace the following components one at a time, in the order shown, restarting
the server each time:
a. DIMMs
b. (Trained technician only) Replace the system board
Note: Each time you install or remove a DIMM, you must disconnect the server from
the power source; then, wait 10 seconds before restarting the server.
1. Reseat the DIMMs; then, restart the server.
2. Replace the failing DIMM.
3. (Trained technician only) Replace the system board