If your in the need to replace your cmos backup battery on your Compaq Evo N610c, N610v, N620c Series Notebook help might be just around the corner and thru the usage of this guide familiarize you with what you will need to solve the error prompts flashing on the screen regarding corrupt cmos. At this point you have come to realize that the notebook is no longer booting your Operating System should that be Microsoft or Linux OS's.

The first thing you will need to be familiar with, is where the cmos backup battery is located on your notebook. You can start by turning over the notebook to the bottom side and adjacent to the Main Battery will be a small rectangular compartment held down by two screws (Mini PCI Compartment Cover).

 These two Phillips head screws must be removed in order to expose the cmos battery that's held in place by a battery holder.

The battery holder accomidates the BR1225 Lithium 3 volt battery, allowing the two potentials of the battery to maintain power to the cmos chip and therefore sustaining the clock/date settings as well as the boot sequence set by the end user. These non rechargeable lithium batteries provide operational function while the notebook is powered off.

After having identified the location of the cmos battery, and having removed the two screws that hold the black rectangular plastic cover, use a non magnetic/plastic tweezer or equivalent probe and pry out the BR1225 battery retained in the Battery Holder. If you don't have access to a Volt meter to determine the diagnosis of the battery, then assume that it  requires replacement, where a replacement would be any brand of battery that suits the BR1225 specs: 3 volts approx 40maH 12mm diameter 2.5mm thickness no wires and no connector. HP refers to call the cmos battery by the name of RTC Disk Cell. To order from HP refer to HP Spare Parts Number 241439-001 (Miscellaneous Plastics Kit Component) Applicable to Compaq Evo Motherboards: 291581-001 (Evo N610c) and 319778-001 (Evo N620c)

Now, while replacements can be for just any electronic store near your home/business, pharmacies also carry these types of batteries, but if your choice is to buy them here on ebay, we recommend buying them from a seller who has other Evo Part integration and has proven themselves to be fully knowledgeable on HP/Compaq Evo Models, whereby most likely they will stock other parts you will need for your Evo such as Hard drives, LCD inverters, LCD display, optical drives, memory and maintenance care products. Below are two sellers and the ebay store links to their Cmos Disk Cells. We have no affliation with them, but as buyers we have purchased from both of them in the past with good success and can recommend them.

cmos battery Evo N610c N610v N620c

cmos battery Evo N620c