Lenovo 7D7Q, Maintenance Manual

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5. Reverse the memory modules between the channels (of the same processor), and then restart the
server. 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.
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 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 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 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 memory modules, and then restart the server.
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 server.
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.
Invalid memory population detected
If this warning message appears, complete the following steps:
Invalid memory population (unsupported DIMM population) detected. Please verify memory configuration is valid.
1. See “Memory module installation rules and order” in
Setup Guide
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.
Hard disk drive problems
Use this information to resolve issues related to the hard disk drives.
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ThinkSystem SR250 V2 Maintenance Manual