The CMOS [Complementary Metal Oxide Semiconductor] battery is a very essential hardware component of the computer. The average computer user knows little or nothing about this hardware part until his computer starts performing strangely. The CMOS battery is known for not consuming too much power and it is responsible for releasing information like disk sizes, computer ports, etc. to the computer; this information is needed for the computer to boot properly or completely and work well.
The CMOS battery is the battery needed to power the CMOS which works with the RAM of the computer, generating the information needed to boot up the computer and run programs.
Due to many reasons, the CMOS battery becomes weak and starts malfunctioning. The average computer user is normally not able to detect this anomaly until it generates into a more serious problem which most times would cost more money to fix. So how do you know when your computer's CMOS battery is getting weak?
- Computer goes off often:
The CMOS battery and the CMOS are needed to keep the computer on. When the CMOS battery becomes weak, you normally would find your computer going off by itself. When this happens at times, we can overlook it because it is not abnormal. However, when it comes on like that for more than say 5 times, you then should check your computer cables. If your cables are okay, then your CMOS battery might just be faulty. A good computer would normally prompt you as it starts booting to check your CMOS battery. Well, if that doesn't happen, consult a qualified computer technician to check it out.
- Slow Programs and Hard Disk Space Problem
The CMOS works hand-in-hand with the RAM which is needed to load programs. When the CMOS battery gets faulty, the CMOS would start working abnormally. This leads to programs/packages loading or opening slowly and finally the computer starts alerting you to clean up your hard drive for space when you hard drive is quite free. When this happens, it is likely that your CMOS battery is faulty. The computer at most times will notify you of the problem as soon as it starts booting. However, if it doesn't do so, consult your computer technician.
You've noticed that the computer is doing a few strange things, but take it to just be one of those 'computer things'. Then one day you turn on the computer, and you notice that the clock is completely wrong. Not only is the time wrong, but the date is too, possibly including the year.
This is a classic example of what can happen when the battery gets low, and it will happen with PC's as well as Mac's. (A Mac doesn't have a CMOS, but it does have a battery, and much of the same applies, just with slightly different terminology.)
Have you ever wondered how the computer manages to keep time even when it is off or unplugged? You turn it on after a week and even if it isn't connected to the Internet, it manages to tell you the correct time. This is just one of the many functions of the battery. Some VCR players, DVD players, or microwaves may do the same thing for a much shorter period of time even if the power supply is interrupted, but these devices also use a battery, which usually doesn't hold the time for as long as a computer will since the battery isn't as powerful.
The clock is one of the more noticeable and observable things that can signal that the computer battery is getting weak. The battery does far more, however, than just power the clock.
Without the battery, the CMOS will not function correctly, which means that the BIOS will lose data. The BIOS is responsible for identifying what programs are on the system, where they are at, what devices are on the system and what drivers they use, and much more. As the battery first starts to become weak, there may be few noticeable signs if the computer is not turned off for any lengthy periods of time. However, if it is turned off for days at a time, these problems may become apparent, and in any event as the battery grows weaker, the problems will almost always be annoyances that can be seen, to the annoyance of the computer user.
The system may not see a printer and give messages to that effect, though the printer has been connected to the computer for years and you never had trouble in the past. The wheel part of a wheel mouse may stop working because the computer will be able to tell that there is a mouse there, but will suddenly not be able to tell what mouse it is, so it will use generic drivers for the mouse. You may try to launch a program but get the message that it couldn't be found, yet when you try to launch the program a second time, there is no trouble in getting it to run.
The good news is that if you have indications that the battery is getting weak, many of the larger computer stores will test the battery for free. It is in their best interest, since if the battery is indeed weak, you are more likely to purchase a replacement there, than to travel to another computer store to get it. If it isn't, you are apt to remember how helpful they were and how willing to assist you. Removal and replacement are simple, and since the battery looks like a much larger version of a wafer digital-clock battery, it is pretty easy to identify.
Not all strange computer behavior can be attributed to the battery. Fairly often, though, it can be. If the battery is getting weak, the best option is to replace it as soon as possible, to prevent further problems and frustrations. It is at the very least worthwhile to keep the battery in mind when troubleshooting computer problems.