System battery

[imaitken]

I am getting a black screen that ends with the message 'Alert!System battery voltage is low.  Use F1 to continue, F2 to go to setup'.  Sometimes when I hit F1 it will continue and run just fine.  Other times nothing happens and I have to turn off the machine(by holding the power button) and when I turn it back on it is OK.
About a week ago we had a thunderstorm.  The computer was off and I turned off the surge protector during the storm.  These messages started after that time.  I don't know if that had anything to do with it.  Do I have to change the system battery?  If so, how do I find out the battery I need and how do I change it?  Is this a serious problem?  Thanks for any help.

[bigtoe]

Sounds like your motherboards battery, called a CMOS battery, is wearing out and in need of replacement... it is a little, round, thick coin like silver battery... available at anyplace, like Radio Shack, Target, KMart, WalMart, or any of the computer stores.... very inexpensive.... Matter of unplugging the computer, taking the case off the computer box, and quickly switching the old and new battery, being sure to have the positive sign ( + ) on one side of the battery put just like the old one was.... likely + side up.... usually held in by a little clip, and battery slides out from under the fragile clip....

Look in any paperwork that came with your comuter, check specs online, or take a peak and see the number on the battery (like CR2302 or whatever)... that way you buy the replacement first, then the switch will only take a couple of seconds.... The computer will hold your settings for a short while, so you definitely don't want to remove the old one and take it shopping to buy the correct replacement....

Batteries last an eternity it seems like, but they do wear out now and then.... nothing recharges them, they just drain extremely slowly so last many years....

Yours likely just happened to be coincidental to the stormy weather....... If you do a web search on the terms listed in your warning message, you'll find some responses that have displays on changing the CMOS battery... or you can do a web search, and there are many web sites offering step by step pictured explanations..... really easy to do... about the same as changing a flashlight battery....

[imaitken]

Thanks Bigtoe.  I knew you would come through for me again.  Don't know what I would do without you when I have a computer problem.  You don't give me a lot of technical stuff,  just help I can understand.

[imaitken]

Bigtoe--It's me again.  Looking at my computer manual, they talk about copying down all the settings on the setup screens so I can reenter them later.  Is this really necessary?  Do you know approximately how long it would be before I lost my settings?  If I am ready with the new battery, I don't think it should take to long to replace the old one.

[bigtoe]

I understand that the system may hold the settings for up to 20 minutes.... it shouldn't take more than 5 or 10 seconds to swap the battery.... I've never worried about copying down any settings when changing a battery, for one reason settings are in many different places... .... and since the process of exchange is so quick when you have the new battery at hand...... For that matter, I've never copied down the addresses, phone numbers, names or email addresses that I have in my data watches when I change the battery on the watch.... they are retained quite adequately for the brief period the power from the battery is absent during the exchange from the battery slot.....

Car radios just don't work the same though, they always have to have power to them or you will need to reset your preset radio channels....Computers are not a problem.... 

**ADDED** Just as an added thought, while you have the cover off the box to be able to exchange the CMOS battery, would be a good time to look to be sure there are no dust bunnies collecting on the cooling fan blades or other components inside the box, having access is a great time to use canned air and blow away the dust..... perhaps hold the cooling fan blades in place with the eraser end of a pencil or with a Q-tip as you quickly blow the air across the blades.... don't want to over spin them or cause undo stress on the blades..... Just something to think about, since you are inside the computer box and have that free view of the interior....

[bigtoe]

I mentioned I have never written down the bios settings, nor have I ever been asked by the computer to reset the bios after a battery change... but you did ask, and if you have the slightest concern, here are the very easy steps to resetting the bios settings to your default settings (and notice, these don't say anything about writing down any settings first.... Most folks wouldn't know what to write down, or what to do with the info IF they needed it, so don't understand why that old alert at sites still exists.... )

To access the bios, when your computer first starts you will see a black screen with white text.

If you look carefully you will see a line that says something like "press del for setup" or some other key (F2 or ESC or tab) this will take you to some cybergod's house where you can make lots of changes to the way your machine works.

You will now be presented with a blue screen with a lot of options on it. The one we want is load optimised/default settings.

Press the F10 key and type y the computer should now reboot.

If every thing went well then your computer will now be up and running.


I don't recommend doing things this way... but several sites recommending doing a hot exchange don't even have you turn off the computer.... just to take the case cover off the box, put the box on its side, use a small knife blade/flat bladed screwdriver, even a wooden skewer and lightly lift up the clip holding the CMOS battery, exchange new for old, close up the case, and continue working....... Almost sounds like servicing an Indy Racer at Indianapolis Racetrack on Memorial Day....  .......

But, I wouldn't be concerned about any of this info as changing the battery very rarely leads to any need to reset default settings... I just add this info in case there is even the smidgeon of any concern on your part. But really it is like making that first cup of coffee with a new coffee maker... once you have done it, you realize it was no big thing and anyone should be able to do it..... 

[imaitken]

OK bigtoe.  Changed the battery, blew out the dust and everything is working fine.  As a matter of fact, the computer sounds quieter than it has in a while.  Thanks again.

[bigtoe]

Very happy to hear that.... You feel ready to build your next computer from the ground floor up, now?? ..

Thanks for giving us the update. You've helped a lot of readers get the courage to tackle the battery replacement, should the occasion arise.... Have a great day.... Al