Replacing the battery on the mb

[bullwinkle]

I need to replace the battery on my mb.  I am concerned about losing the CMOS settings in doing so.  I was told that if I kept the power active on the board when making the change, that there would be no ramifications.

Is this true?

[BC_Programmer]

The CMOS Settings don't store anything particularly valuable, Except perhaps the time.

[bullwinkle]

I was under the impression that replacing the battery without the power on would reset certain systems on the mb.  So are you saying that it really makes no difference if the mb is powered on or off when changing the battery?

[patio]

It takes the BIOS back to it's fail-safe settings....which 97% of the time are the correct ones anyways...

And you should do it with all power removed...never with power to the board.

[Salmon Trout]

Removing the CMOS battery may or may not cause stored settings to be lost. The battery provides the power to run the real time clock. On older systems it also provided the small amount of charge needed to maintain the non-volatile BIOS memory, which remembered BIOS settings between reboots. On modern systems this information is typically stored in flash memory and does not require a charge to be maintained. As we do not know the age of the motherboard, it is impossible to say whether settings would be lost in this case.

Personally I would never do anything on the motherboard at all including changing the battery while the power was on. I would power down the machine and remove the power cord from the PSU.

[bullwinkle]

Thank you.  The guy who told me to keep the power on fixes computers for a living, so I figured he knew what he was talking about.  This is an old mb so the BIOS memory will probably be erased if all power was gone, which is probably why he told me to keep the power on while replacing the battery.

If the BIOS memory is erased, how difficult would it be to reestablish it with an old system?  I have an ASUS A8N-SLI board.

Also - I cannot find beep codes for this board.   I googled it but cannot find a listing.  I'm getting 4 short beeps on bootup - with a CPU Fan statement.  Pushing F1 continues the boot without a problem.

[Salmon Trout]

As Patio says, the BIOS settings would revert back to fail-safe settings. They would not go "blank".

I guess it's your choice whether you leave the power on. I think you would be crazy. Never mind what your friend says. If I had a dollar or a euro for everybody I have heard of who killed their system because a "friend" said something was OK, I'd probably have enough to buy a motherboard. You only have to drop a battery or accidentally short something or dislodge a RAM module to kill the motherboard. Since you would be gaining nothing by leaving the power on, why do it?

[Spoiler]

You have to go into the settings for the bios. Look for the chipset settings. In that menu you will find a setting that lets you disable the failure on boot of the fan. This will let you by pass the error you are getting.

That board has a chipset with a small fan on top of it. The fan has failed and it is letting you know that your MB has a chance of over heating the chipset below the fan.

This is a old board and when you replace the battery it will default back to the warning about the fan. Don't worry about it. Just change the battery. When it comes backup you will still get the error. Just hit F1 and boot up. Than set your clock. After do a reboot and go into the bios and disable the chipset fan warning.

[patio]

If he advised that and he fixes PC's for a living perhaps he is considering job security...just sayin.

[Salmon Trout]

If he advised that and he fixes PC's for a living perhaps he is considering job security...just sayin.

Exactly. My advice to everyone is be cautious of advice from friendly helpful friends who fix computers for a living.

[DaveLembke]

Only battery hot swap i ever did was for my Honda where disconnecting battery would render car stereo useless until brought back to dealer to have them reset it. Its a anti stereo theft feature. I had to place a 12V jumper pack on the cars posts while swapping out a weak battery and installing new battery. I was successful and got the new battery installed in my car and didnt lose my stereo...

However on a computer, modern computers being reset back to default for BIOS generally is not a problem 99% of the time. Its only if you have a strange build where you have legacy features enabled for say a old Adaptec SCSI controller for a 18GB HDD and lose that setting and then the system doesnt boot because the legacy SCSI controller setting isnt set correctly that you run into problems or a system of the 286 and 386 era that you had to manually configure the hard drive to how many heads and sectors and cylinders and all that mess years ago that a reset BIOS would make for extra work.

I would never swap a CMOS battery on the fly. Its way too dangerous to have a coin cell 3V battery pop out and cross something killing the system. If you had a system that was highly configured or worried about losing the settings, its best to go into the BIOS and take screen shots with a camera pointed at monitor of the settings of each page or write them down to set it back the same way then swap the battery out with system unplugged from wall so even the soft power is not present on the board in off state.

[patio]

This is being over-thought...remove all power...then remove and replace the battery and powerup.

[Geek-9pm]

Yes, it is being over thought. We could ask the UN  assembly to rule on this.
OR:
Save and restore BIOS settings?

 

[bullwinkle]

OK guys, thank you very much for the input - and the conversation.

BTW does anyone have a link to ASUS mb beep codes?  When I google it all I get are personal questions about the codes being answered.  There should be a list of them somewhere.

UPDATE:  I looked up the BIOS on my system, Phoenix Award and was able to google the beep codes - although none of them match what I'm getting (4 short beeps with no pause).

[DaveLembke]

UPDATE:  I looked up the BIOS on my system, Phoenix Award and was able to google the beep codes - although none of them match what I'm getting (4 short beeps with no pause).

Have you removed all drives, gone down to a single stick of RAM, and removed video card (only if the system has integrated video to fall back on ), and tried a minimal boot? If you get same results, swap to a different RAM stick, if you get same results again try a different RAM slot like slot 1 vs slot 0.

*Is this the same system that needed the battery replaced on the BIOS, now all of a sudden doesnt want to boot? If so.... what happened between last successful boot and when it failed, what action was carried out, any changes to hardware etc.