Serial-Device Problems - Lenovo ThinkSystem SR645 Maintenance Manual

2. Select System Settings ➙ Devices and I/O Ports ➙ MM Config Base; then, modify the setting to
increase the device resources. For example, modify 3 GB to 2 GB or modify 2 GB to 1 GB.
3. Save the settings and restart the system.
4. If the error recurs with the highest device resource setting (1GB), shutdown the system and remove
some PCIe devices; then, power on the system.
5. If the reboot failed, repeat step 1 to step 4.
6. If the error recurs, press Enter to access System Setup Utility.
7. Select System Settings ➙ Devices and I/O Ports ➙ PCI 64–Bit Resource Allocation, then; modify
the setting from Auto to Enable.
8. If the Boot Device does not support MMIO above 4GB for Legacy Boot, use UEFI Boot Mode or remove/
disable some PCIe devices.
9. DC cycle the system and ensure the system is enter UEFI boot menu or the operating system; then,
capture the FFDC log.
10. Contact Lenovo technical support.
A Lenovo optional device that was just installed does not work.
1. Make sure that:
• The device is supported for the server (see
• You followed the installation instructions that came with the device and the device is installed
correctly.
• You have not loosened any other installed devices or cables.
• You updated the configuration information in system setup. When you start a server and press F1 to
display the Setup Utility. Whenever memory or any other device is changed, you must update the
configuration.
2. Reseat the device that you have just installed.
3. Replace the device that you have just installed.
4. Reseat the cable connection and check there is no physical damage to the cable.
5. If there is any cable damages, then replace the cable.
A Lenovo optional device that worked previously does not work now
1. Make sure that all of the cable connections for the device are secure.
2. If the device comes with test instructions, use those instructions to test the device.
3. Reseat the cable connection and check if any physical parts have been damaged, .
4. Replace the cable.
5. Reseat the failing device.
6. Replace the failing device.

Serial-device problems

Use this information to solve problems with serial ports or devices.
• Number of displayed serial ports is less than the number of installed serial ports
• Serial device does not work
Number of displayed serial ports is less than the number of installed serial ports
Complete the following steps until the problem is solved.
1. Make sure that:
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https://static.lenovo.com/us/en/serverproven/index.shtml ).