PowerEdge: How to Replace a CMOS Battery

Summary: To replace a CMOS battery, remove the air shroud, disconnect and remove any expansion cards, locate the battery socket, and carefully pry out the CMOS battery. After installing a new CMOS battery, you must reinstall the expansion cards, install the air shroud, and restore the BIOS settings, ensuring the battery is operating properly and the correct data and time are set in the System Setup. ...

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Instructions

Instructions:

Note: If your CMOS battery has already failed, you must set the BIOS settings manually again or restore from a previous backup.
  • Remove the air shroud
    • Disconnect the power or data cables from the expansion card riser (if applicable)
    • Remove the expansion card risers (if installed)
    • Remove the PCIe expansion cards (if installed)
  • Locate the battery socket
CAUTION: To avoid damage to the battery connector, you must firmly support the connector while installing or removing the battery.
  • Use a plastic scribe to pry out the system battery

Plastic scribe presses on release to remove the CMOS battery from its socket

  • To install a new system battery, hold the battery with the positive side facing and slide it under the securing tabs
  • Press the battery into the connector until it snaps into place

CMOS battery installation

Reassemble the system

  • Install the low-profile PCIe cards (if applicable)
  • Install the expansion card riser and connect the power or data cables to the expansion card risers (if applicable)
  • Install the air shroud

Verify the system

  • While booting, press F2 to enter the System setup
  • Ensure that the battery is operating properly
  • Enter the correct data and time in the System Setup Time and Date fields
  • Restore the BIOS settings (if applicable)
  • Exit the system setup

Example Video

How to remove or install a System battery on PowerEdge R650 

Duration: 00:01:24 (hh:mm:ss)
When available, closed caption (subtitles) language settings can be chosen using the CC icon on this video play

 

 

Affected Products

C Series, HS Series, Modular Infrastructure, Rack Servers, Tower Servers, XE Servers, XR Servers, OEM Server Solutions
Article Properties
Article Number: 000234357
Article Type: How To
Last Modified: 19 فبراير 2026
Version:  10
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