Memory 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.
  • Go to the Lenovo support website at the Lenovo Support Portal to check for technical information, hints, tips, and new device drivers or to submit a request for information.
Table 1. Memory problems and actions.

The memory problems and actions table with one level of row and column headers.
Symptom Action
The amount of system memory that is displayed is less than the amount of installed physical memory.
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).
  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:
    1. DIMMs
    2. (Trained technician only) Replace the system board
Multiple rows of DIMMs in a branch are identified as failing.
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
Parent topic: Troubleshooting by symptom