Locate your CMOS battery
Open the computer case and find the battery on the computer motherboard,verify that it will be accessible and that it can be removed. Mostcomputers today use a coin cell CMOS battery as shown in the image tothe right.
If you are unable to locateyour CMOS battery you will need to refer to your motherboard orcomputer documentation and/or contact your computer manufacturer for additional assistance in locating it.
Obtain battery information
Unfortunately,most manufacturers will not list the exact type and model of your CMOSbattery; therefore, once you have located the battery, write down allinformation about the battery (Voltage, chemistry, wiring, andpackaging). If possible, remove the battery and take it to the locationyou plan on purchasing a new battery from.
Additional buying information can be found on our battery buying tips page.
Removing the battery
Caution: While in the computer make sure you're aware of Electro Static Discharge (ESD), your computer is off, and that you're properly grounding yourself. Especially before removing the battery.
Ifyou're computer is using a coin cell battery similar to the aboveexample picture. Removing the battery is relatively simple. Simply useyour fingers to grab on the edge of the battery and pull it up and outof the container holding it. Some motherboards have a clip holding thebattery down. If your computer has this clip you may need to use onehad to move the clip up and the other hand to pull the battery out.
Unfortunately,not all CMOS batteries are removable; some manufactures will only allowa replacement battery to be added. If you're not using a coin cellbattery and are not able to determine how to remove it refer to yourmotherboard or computer documentation and/or contact your computer manufacturer for additional assistance in removing the battery or how to insert a new replacement battery.
Userswith computers that do not have removable batteries only options toinstall a new battery will most likely also need to set a jumper when adding the new battery into their computer.
Insert the new battery
Once you have purchased a new battery, remove the old battery (as instructed above) and replace it with the new battery.
Enter CMOS values
Oncethe battery is replaced turn on the computer and enter all values backinto CMOS or set the values back to the default settings.