Lenovo 7D31, Maintenance Manual

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2. Install the PMEMs back to the target system, and upgrade system firmware to the latest version without
entering Setup Utility.
3. If the problem persists, overwrite PMEMs with the following ndctl command.
ndctl sanitize-dimm --overwrite all
4. Monitor the overwrite status with the following command.
watch -n 1 “ipmctl show -d OverwriteStatus -dimm”
5. When seeing all PMEM
OverwriteStatus=Completed
, reboot the system and see if the problem persists.
Monitor and video problems
See this section to solve problems related to a monitor or video.
• “Incorrect characters are displayed” on page 241
• “Screen is blank” on page 241
• “Screen goes blank when you start some application programs” on page 241
• “The monitor has screen jitter, or the screen image is wavy, unreadable, rolling, or distorted.” on page 241
• “The wrong characters appear on the screen” on page 242
• “Management controller remote presence cannot work” on page 242
Incorrect characters are displayed
Complete the following steps:
1. Verify that the language and locality settings are correct for the keyboard and operating system.
2. If the wrong language is displayed, update the server firmware to the latest level. See “Firmware
updates” on page 8.
Screen is blank
1. If the server is attached to a KVM switch, bypass the KVM switch to eliminate it as a possible cause of
the problem: connect the monitor cable directly to the correct connector on the rear of the server.
2. If the server installed with the graphical adapters while turning on the server, the Lenovo logo displays
on the screen after approximately 3 minutes. This is normal operation while the system loads.
3. Make sure that:
• The server is turned on and there is power supplied to the server.
• The monitor cables are connected correctly.
• The monitor is turned on and the brightness and contrast controls are adjusted correctly.
4. Make sure that the correct server is controlling the monitor, if applicable.
5. Make sure that the video output is not affected by corrupted server firmware; see “Firmware updates”
on page 8.
6. If the problem remains, contact Lenovo Support.
Screen goes blank when you start some application programs
1. Make sure that:
• The application program is not setting a display mode that is higher than the capability of the monitor.
• You installed the necessary device drivers for the application.
The monitor has screen jitter, or the screen image is wavy, unreadable, rolling, or distorted.
1. If the monitor self-tests show that the monitor is working correctly, consider the location of the monitor.
Magnetic fields around other devices (such as transformers, appliances, fluorescents, and other
Chapter 5
.
Problem determination
241