** It is RECHARGABLE type NOT Watch type battery **
The CMOS battery (or the motherboard battery) has a unique purpose in a computer. This page will explain what the battery is, how to change the CMOS battery and how to remove the CMOS battery and a range of other things to do with that little computer battery inside your motherboard.
The CMOS is a little bit of RAM that stores all the BIOS information so that each time the computer restarts or powers on, the computer can remember this information. You can find out more information about the CMOS and BIOS in their relevant pages.
So you are asking what does the CMOS battery have to do with all of this? Well this battery in the motherboard, is what powers the CMOS RAM when the computer is turned off. So that it doesn't lose all your BIOS information.
Desktop
If you didn't have this battery, then each time you turn on your computer, the BIOS settings would reset and you would need to setup your BIOS again. Your computer will function but everything in your BIOS, such as the boot order, and the time and date, and other functions will reset.
Thus this little CMOS Battery proves more important then it looks. If your battery dies as they do after a while then you can purchase another one. They cost a few dollars at your local supermarket, newsagent or chemist.
Removing the CMOS battery is a way to reset the CMOS password. Read more here.....
To remove the CMOS battery is quite a simple task, simply press the little silver thing back, and release the battery. To insert the battery again just push the battery and it will fall back in.
BIOS Setup Utility
The computer BIOS setup utility (also known as the CMOS setup) is the place where you can change a few basic computer hardware settings. The BIOS and CMOSoften get confused but there is quite a difference.
The BIOS contains all the settings and the CMOS memory is a piece of RAM that remembers all the info.
In the case of many computers pressing delete or F10 in the booting process will bring you to the BIOS setup utility. If these don't work, then your computer will specify on startup such as (press ******* to enter setup) or it will be mentioned in your manual. There is no harm in looking at the setup, so find your key and have a look (just make sure you don't save on exit).
When your in the setup, you can change many options. You can change the order of booting, which device do you want the computer to boot to etc. You can decide whether to disable particular devices (such as onboard sound or network cards). You can change the date or time and you can also reset the CMOS back to factory settings. This will return the BIOS back to default, which isn't the greatest idea in the world unless you know what your doing.
The settings in the BIOS depend on each manufacturer. Here I will give you a little run down on the Tabs and what they could have in them.
Advanced Tab
In the advance tab you often find information on the IDE configuration, the Floppy Configuration, the Boot Settings configuration. You can further investigate by pressing enter over the IDE configuration and then looking at the items listed. It will have all your hard drives and cd/dvd drives listed here. If you have two hard drives connected then two will show up here.
This is a great place to check if your hard drive is being recognized. If the new hard drive or cd/dvd drive is not recognized in here, then your operating system will definetely not find it. If your hard drive is recognized here but not by windows then there is some problem with your operating system, but not your computer.
You can zoom in even more by pressing enter and have a look at a specific hard drive in detail. You can see its exact size, the vendor and the mode and other specifications.
Power Tab
The power tab is self-explanatory. It just gives you power options that you can change. I would recommend leaving these as they are.
Boot Tab
The boot tab of the BIOS setup gives you all the options for when you boot up. You can order the preference in booting. You can choose whether you want to boot from the Floppy Drive, CD drive, or hard drive and in what order. This is probably the most changed setting in the BIOS setup. I would also leave as they are unless you need to specifically boot from another location.
In more recent computers you can change it to boot via a network, or through USB. Check out this page on the boot process for more information on what a computer does when it starts.
Security Tab
In this tab you can change all the passwords, or assign passwords to the BIOS. This can be a risky thing to do because you could forget your password, but if you do there is a way of fixing it. Follow this tutorial to learn how.
Exit Tab
The Exit tab is more completed then you would expect. There are a number of options here. You can exit saving your changes, you can exit discarding changes, you can load optimal defaults and also the failsage defaults. I wouldn't recommend going back to these defaults as they will change everything, unless you know what your doing.
This ends this page on the Bios Setup. I hope you learnt some valuable information. What I showed you was a really basic Bios utility. Most of your computers will have many more functions like turning off integrated graphics and sounds and making very precise changes.
One word of advice don't change anything unless you know what your doing and if you accidently do then just ext without changes.
Reset Bios Password
So what do you do?
Reset the BIOS Password! Resetting the BIOS password is actually easier then it sounds. Basically you have two options. You can take out the CMOS battery (which remembers the BIOS information) or in more modern machines you can move a little jumper on the motherboard which is mostly called Clear CMOS, or reset BIOS to defaults or something.
1. Take the CMOS Battery Out
Firstly we will look at the CMOS battery way, which is the way all the oldies had to do it. First, shut down your computer and remove the power cable. Then open up the computer and then locate the CMOS battery on your motherboard.
Next you will need to press in the little metal side in and flick the battery out. Leave the battery out for 20 - 30 minutes. Then re-insert your battery, plug in the power cable, and turn your computer on.
Press the key to enter your BIOS setup and then proceed to setup your BIOS accordingly.
Now for the second option in resetting the BIOS password. This option is a lot quicker then the first.
2. Use the Clear CMOS Jumper
First you will need to shut down your computer, take out the power cable and open up your pc. Then you need to look on your motherboard, for a few pins with a jumper on them. Don't just take out random jumpers make sure you find the right one.
Remember not every motherboard will have the pins. Hopefully you can find some clear CMOS pins that look something like the picture below. This picture below is a really zoomed in picture of the one above (you can see the CMOS battery on the right there).
Can you see the small text on the motherboard explaining the clear CMOS jumper. It says: 1-2 Normal, 2-3 CLEAR CMOS. That means if you leave the jumper on pins 1-2 then the BIOS information will still be remembered. But if you change the pin to 2-3 then all the BIOS information is cleared and forgotten.
So if you want to reset the BIOS password just place the jumper on pins 2-3 for about 1 minute then place it back on pins 1-2 and the process of resetting your bios is complete.
So now you know how to reset the BIOS password.
GOOD LUCK
