Memory problems

Table 1. Memory problems and actions

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 IBM 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.
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. Make sure that: No error LEDs are lit on the operator information panel. The memory modules are seated correctly. You have installed the correct type of memory. All DIMMs are enabled. The server might have automatically disabled a DIMM when it detected a problem. Check the POST error log for error message 289: If a DIMM was disabled by a system-management interrupt (SMI), replace the DIMM. Run memory diagnostics (see Running DSA Preboot diagnostic programs). Make sure that there is no memory mismatch when the server is over the minimum memory configuration (one 1 GB DIMM) and that you have installed the correct number of DIMMs. Reseat the DIMMs. Replace the following components one at a time, in the order shown, restarting the server each time: DIMMs (Trained service technician only) System board
Multiple DIMMs in a channel 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. Reseat the DIMMs; then, restart the server. Replace the lowest-numbered DIMM pair of those that are identified; then, restart the server. Repeat as necessary. (Trained technician only) Replace the system board.