Memory problems

See this section to resolve issues related to memory.

Displayed system memory is less than installed physical memory

Complete the following procedure to solve the problem.

Note: Each time you install or remove a memory module, you must disconnect the solution from the power source; then, wait 10 seconds before restarting the solution.
  1. Make sure that:
    • No error LEDs are lit on the operator information panel.

    • No memory module error LEDs are lit on the system board.

    • Memory mirrored channel does not account for the discrepancy.

    • The memory modules are seated correctly.

    • You have installed the correct type of memory module.

    • After changing or replacing a memory module, memory configuration is updated accordingly in the Setup Utility.

    • All banks of memory are enabled. The solution 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 solution is at the minimum memory configuration.

  2. Reseat the memory modules, and then restart the solution.

  3. Check the POST error log:

    • If a memory module was disabled by a systems-management interrupt (SMI), replace the memory module.

    • If a memory module was disabled by the user or by POST, reseat the memory module; then, run the Setup utility and enable the memory module.

  4. Re-enable all memory modules using the Setup utility, and then restart the solution.

  5. (Trained technician only) Install the failing memory module into a memory module connector for processor 2 (if installed) to verify that the problem is not the processor or the memory module connector.

  6. (Trained technician only) Replace the system board.

Multiple memory modules in a channel identified as failing

Note: Each time you install or remove a memory module, you must disconnect the solution from the power source; then, wait 10 seconds before restarting the solution.

Complete the following procedure to solve the problem.

  1. Reseat the memory modules; then, restart the solution.
  2. Remove the highest-numbered memory module of those that are identified and replace it with an identical known good memory module; then, restart the solution. Repeat as necessary. If the failures continue after all identified memory modules are replaced, go to step 4.
  3. Return the removed memory modules, one at a time, to their original connectors, restarting the solution after each memory module, until a memory module fails. Replace each failing memory module with an identical known good memory module, restarting the solution after each memory module replacement. Repeat step 3 until you have tested all removed memory modules.
  4. Replace the highest-numbered memory module of those identified; then, restart the solution. Repeat as necessary.
  5. Reverse the memory modules between the channels (of the same processor), and then restart the solution. If the problem is related to a memory module, replace the failing memory module.
  6. (Trained technician only) Install the failing memory module into a memory module connector for processor 2 (if installed) to verify that the problem is not the processor or the memory module connector.
  7. (Trained technician only) Replace the system board.

Invalid memory population detected

Invalid memory population (unsupported DIMM population) detected. Please verify memory configuration is valid.
If this warning message appears, complete the following steps:
  1. See Memory module installation guidelines to make sure the present memory module population sequence is supported.
  2. If the present sequence is indeed supported, see if any of the modules is displayed as “disabled” in Setup Utility.
  3. Reseat the module that is displayed as “disabled,” and reboot the system.
  4. If the problem persists, replace the memory module that is displayed as “disabled.”