How often should I replace my CMOS battery, and what does it do, anyway?

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It's been so long since a computer of mine has had the CMOS battery die, that I honestly couldn't tell you what would happen on any of the computers I currently have. But, as you said, back in "the good old days", that battery kept every BIOS setting you had, and removing it would reset everything to the manufacturer's default.

While most systems use a standard CR2032 battery, I did see one system years ago which used some customer-looking battery that was actually soldered to the motherboard. Needless to say, we didn't replace it when it died.

Actually, I found out that in Laptops you Really never will have to replace the battery, as I noticed one time when I had to remove the CMOS Battery that the laptop uses it's Battery Pack for thismatter also, I do not know if this is a standard for all laptops but my Acer Does uses it's own battery instead of a CMOS CR2032 battery

A random thought here. I have had computer troubles fairly recently where one trick recommended was to re-seat the CMOS battery. Is there anything else that the battery can influence?

It should be noted that the CMOS battery may not be used at all when the machine is plugged in (or in the case of a laptop, when the main battery is present).

Therefore its only function would be to keep the time if the computer was unplugged or the laptop's main battery removed.

I have an older computer and the CMOS battery powers the BIOS 24/7. It died. I would replace it if I knew were it was. Just can't find it.

I removed my CMOS battery from my Mecer Laptop for +- 10 min to flash the BIOS as i had a Worm that was corrupting my computer. I first tried a fresh re-installation. This did not work. Now that i removed my CMOS - thinking that the worm might be corrupting my BIOS, My Screen just stays off, No POST when booting up. My CPU runs and the Battery light does come on. The HDD light does flicker when the laptop is turned on. How can i get my screen back on and how can i use my Laptop now. NB: I did recal removing the RAM so i could get to the CMOS battery.

I realize this may be a old thread, but I'm haveing a major problem with my cmos battery. It keeps dyeing, Or if the battery voltage drops any, it won't boot up all I get is a blank screen. When I put in a fresh battery, it works fine for about 2 weeks or so, Then does the same thing. I tried to flash my bios and it came up with "There was a unknown error, accessing a unknown file" I'm ready to throw this thing out the window. please help

Hi, When I did boot up the laptop, the CMOS was in place. Everything was in place as it should be. NOW THAT'S ASTOUNDING. i just dont understand why the laptop screen doesn't come on. By removing the CMOS and putting it right back, Would this remove the BIOS? Any Other Suggestions.

I have a question, I was in my bios I left my computer for a minute,my little nephew pressed or held down the enter key and my computer locked up, I've tried using the passwords that was set, my computer dosen't recognize them anymore, can you tell me what has happen or if I have any recourse ? I was thinking I could change my cmos battery .... after reading some threads I don't think so

i was having problems with my software shutting down for no reason, i replaced the cmos battery, and now everything is working with no crashes.i wasnt sure if this would fix the problem, but i had to try the cheapest way first. it was simple to replace, and i got it in a two pack at walmart for 1.99 in the watch section. just glad it wasnt somthing major.

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