| You might ask "What is the 3V motherboard battery"? | | | | parts myself the first thing I did was look at the BIOS |
| On the majority of PCs the motherboard holds a +3 | | | | settings. It was soon obvious that the BIOS settings |
| Volt Lithium Battery which is used for two functions. | | | | were corrupt (wrong bus speed). I put a volt meter on |
| Firstly it keeps the computer time updated. Secondly, | | | | the battery and sure enough it was reading 2.2 volts. |
| on older PC's it keeps the BIOS settings (Low level | | | | I could easily have spent a fortune replacing the |
| start-up instructions) in memory. | | | | motherboard, the memory, the processor etc when it |
| By the way, on most modern PC's the time is updated | | | | all came down to 2 dollar battery. What's more is |
| from the web. The 3V battery just maintains the time | | | | these batteries are easy to get. What you need is a |
| when the PC is powered off. This is useful as the | | | | CR2032 available at most hardware stores like home |
| motherboard clock is not very accurate, easily losing a | | | | depot and I've even seen them sold in Safeways. Of |
| couple of minutes per day. | | | | course every reputable computer store should stock |
| If you have your PC case off you will see something | | | | them. Just check to make sure that your PC uses a |
| on the motherboard that looks like a small thick silver | | | | CR2032 before you go to the shops! |
| coin. That is the battery. There are other types of | | | | I run a PC repair business in Vancouver. I always tell |
| battery used on newer machines (Ni-Cad, NVRAM) | | | | people who call with clock problems to check their |
| but these much less frequently found and so I won't | | | | motherboard battery first before calling me round. For |
| discuss them further. | | | | most people it's easy to check and easy to replace. I |
| So how long does it last? Anything from 3 to 9 years | | | | don't want to make money from fixing something so |
| if you search this question on Google. Everyone has a | | | | simple. |
| different opinion. In my experience about 6 years is the | | | | So how do you replace it? In most cases very easily. It |
| average. It's basically a large watch battery and is | | | | should be easily removed with some tweezers, just be |
| constantly supplying a trickle of power to the | | | | careful not to short circuit the + (top) and - (bottom). |
| motherboard. Just like many of my watches the | | | | Also be careful not to over stress the clamp that holds |
| battery can last 2 years or up to 6 years (Fossil | | | | it in place. After you have replaced the battery the |
| watches don't seem to last long for me for some | | | | BIOS settings will be set to default. This means that if |
| reason). How long was the PC in the warehouse | | | | you had any special settings (boot sequence, |
| before it was delivered? And, how long was the | | | | overclocking etc) you will have to go into the BIOS |
| motherboard in the warehouse before it was installed | | | | (usually F2 or DEL whilst booting) and reset them. This |
| in the PC? | | | | is a good opportunity to reset the time and date also. |
| Why is this important? If you have a relatively new PC | | | | Use the arrow keys and return to change these |
| the only problem you will get are error messages | | | | settings. |
| relating to the clock on start up. No big deal. If your PC | | | | So, in summary, if you have a PC which is showing |
| is older then a low battery could be a nightmare. I had | | | | clock errors or BIOS problems look first at the little 3 |
| a PC which once every few months refused to boot. | | | | volt battery. It could save you a fortune. Happy |
| Rather than take the PC in for repair or start replacing | | | | computing! |