• If the problem remains, replace the operator information panel.2. Make sure that:• The power cords are correctly connected to the server and to a working electrical outlet.• The LEDs on the power supply do not indicate a problem.3. Reseat the power supplies.4. Replace each power supply, restarting the server each time:• DIMMs• Power supplies5. If you just installed an optional device, remove it, and restart the server. If the server starts, you mighthave installed more devices than the power supply supports.Server does not power onComplete the following steps until the problem is resolved:1. Check the event log for any events related to the server not powering on.2. Check for any LEDs that are flashing amber.3. Check the power LED on the system board.4. Reseat the power supply.5. Replace the power supply.Server does not power offComplete the following steps until the problem is resolved:1. Determine whether you are using an Advanced Configuration and Power Interface (ACPI) or a non-ACPIoperating system. If you are using a non-ACPI operating system, complete the following steps:a. Press Ctrl+Alt+Delete.b. Turn off the server by pressing the power button and holding it down for 5 seconds.c. Restart the server.d. If the server fails POST and the power button does not work, disconnect the power cord for 20seconds; then, reconnect the power cord and restart the server.2. If the problem remains or if you are using an ACPI-aware operating system, suspect the system board.Memory problemsUse this information to resolve issues related to memory.• “Displayed system memory less than installed physical memory” on page 210• “Multiple rows of DIMMs in a branch identified as failing” on page 211Displayed system memory less than installed physical memoryComplete the following steps until the problem is resolved: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.210 ThinkSystem SR650 Maintenance Manual