This video should help you resolve a lot of computer problems. Drop us a LIKE 👍

I'm surprised motherboard manufacturers haven't come up with a design that detects low voltage on the battery and gives a meaningful warning.

CR2032 stands for: C - type of battery: lithium , voltage 3V R - shape: round 20 - diameter: 20mm 32 - height: 3.2mm

Thank you. About a week before your video my Intel motherboard wouldn’t boot or power on. Replaced the CMOS battery and it worked then failed again. I forgot to clean the metal contacts. Cleaned and fixed. Also did a deep cleaning of dust and dog fur from my fans and motherboard. Great 👍 video

This video is extremely useful and important , thank you for making it. Many, many people, think that a worn out or faulty CMOS battery will simply set the BIOS values and date/time to their default, and that you can get away with it if you enter the correct values each time you turn on your PC. This , unfortunately, is simply NOT true.... I 've been building PC rigs for more than 20 years for friends and relatives and here's maybe the funniest story that i have to share : i once put together a retro gaming xp pc for myself. Brand new hdd, RAM, good quality PSU, all other hardware known to work PERFECTLY, and just to have everything in top shape, i decided to install a BRAND-NEW CMOS battery, from a very reputable and well-known company i might add...well, to cut a long story short, the pc kept crashing at the same exact point when it was loading windows XP, with me banging my head on the desk trying to figure out what was wrong....after swapping every hardware i could , from all the obvious ones to all cables, and even trying to loosen up the motherboard screws (!), i was ready to give up, when it occured to me to swap the brand new CMOS battery that i had installed with an old battered one i had laying around...and , lo and behold, the PC booted up perfectly!!! the funniest thing is , that the same "faulty" new CMOS battery worked just fine in another motherboard.....!! Now i 've seen a lot of weird stuff, but never an...incompatibility of a certain motherboard with a specific CMOS battery! Life as a PC tech never ceases to amaze me ....

Great video, thanks Brian. I've just changed the CMOS battery on my brothers old XP dual core Pentium 4 PC. There the dying CMOS battery first manifested via errors with delayed writes to the D: drive, then boot errors, but BIOS and time settings were still remembered, so it took a while before I started to suspect the battery.

There's a number of strange behaviors that can occur when the batteries are dying. Usually the most obvious is the time/date problem. It's usually a CR2032 battery which you can often find at the dollar store.

Thank you very much! A very important and useful video indeed!

Good info as usual Brain ,keep up the good work.

EXCELLENT VIDEO REMINDER TO THOSE WHO OVERLOOK THEIR CMOS BATTERY, AND USE THEIR PC AND LAPTOP ON SUCH A REGULAR BASIS.

I was about to buy a new PSU because my PC keeps on shutting down and this video saved me a ton of money! Thank you so much!

I've seen some systems that will refuse to power on with a dead CMOS battery primarily the Prebuilt ones like the old Compaq Presarios from around the Windows ME era are one example if the CMOS battery dies it won't turn on. Carey Holzman had one as soon as he put a new battery in the thing sprang to life without even having to hit the power button

When the CMOS battery is ending it's life it will still show close to 3 volts by itself. But in the motherboard the voltage will be much lower due to current drain. Best to measure the CMOS battery in the motherboard first before taking it out of it's holder. Measure between the + side on top of the battery in its holder and the board ground at a metal connector shield at the back side of the board. If the battery is at 3 volts or more it has a lot of life left. If it's down to 2.7 volts replace it for good measure before trouble starts.

I had a Packard Bell system bought in Portugal 10 years ago. Recently built a new system but the PB was working fine since new. Battery lasted through all the moves etc. Came back to UK 5 years ago.

My father always measures both votage and milliamps on these batteries because voltage may be right (3v) but if you can also have low milliamps and this causes malfunction too.

Wow 😲this is the video that I exactly want. Nice one mate.

Good to know this probably was an issue a few years back that old pc reviving had problems booting - always a spare handy

Excellent. Thank you. Cheers, Harry.

Nice to find this helpful video. I just had to change my CMOS battery. Check old battery with Multimeter and was 0.04 Volts jeez that outa 3.2 Volts for new one. Big difference.

i've noticed mostly on msi motherboards that it gets glitchy during POST or does not POST entirely. also, after replacing the cmos batter and the issue persist, usually its the clock crystal that needs replacement.

Can dying CMOS Batteries also cause BIOS settings not being changed/saved? On my previous PC that I used from August 2015 to January 2020 the mainboard started to have issues persisting settings the last year (2019) or so, although booting up wasn't a problem. It once reset to default values after OC instability and then I wasn't able to reconfigure my settings. Only every now and then when taking the battery out for a bit I could set some things IIRC. Unfortunately I didn't get to searching and buying a new CMOS battery and don't remember having checked the voltage (although I was able to), I just worked around this by installing a program for CPU OC from Windows and letting the RAM run at default 1333 MHz instead of the 1866 MHz XMP profile. And then I built a new PC and sold the previous one, so didn't do further troubleshooting. Could it have been a dying CMOS battery or was it something else going wrong with the mainboard? If so, what could it have been?

I've gone down to my dollar tree store and purchased a CR2032 for only a buck! Last few times they've had the Panasonic brand!!! I figure if I'm gonna crack my case open for a good blow-out, I might as well check the CMOS battery!!! When I was doing tech work, I'd go to a location and see customers with their tower PC on the floor. WORST place to put a PC....sucks in dust and whatnot!!! Then, if it was a lawyer's office, they'd have crap piled everywhere!!!...pretty much suffocating the airflow to the PC!!! Several times, the pc's contained sooo much dust that the user would complain that the PC was running slow!!! And I'd say...your computer is running slow because the heatsinks are clogged with dust and your processor is throttling down to keep from burning itself out due to lack of free airflow. I would usually get a blank stare in return. 😏

I worked at a company that had a PC based piece of medical equipment. Whenever we got a unit in from the field, we automatically changed out the battery. And we carried batteries in the field.

Great video thanks for the info

Well done, Brian. Brilliant as always. Computer BIBLE. A good PC life begin with "CR 2032". Have a nice smooth boot to all.

It's funny you just now made a video on this topic, as i not more than an week ago had to change my battery. 😁👍

Hi Brian, I have an old computer which I haven't started for about 2 years old. Should I change the CMOS battery before I boot it up since it hasn't been powered on in 2 years?

Brilliant, thank you!

Is it possible for the battery to fall out just by a shaky desk? And Is there a way (without using electrical tape or something) to make sure it stays in place?

You don't have to remove the battery to test. The + is on the top so touch red lead to top and black lead to metal chassis

Great tip,i've used maxell for cr 2032,thanks for your video.

I was always wondered why don't motherboards use the internet to set time and date in the bios. So when u turn on the pc it asks to connect to the internet and sets the bios and date time and eliminate the battery fully.

Thanks for the reminder!

Thank you for the video! ☺♥

Usually, unless the BIOS chip is coded really wonky, the computer will know when something isn't right upon boot-up and it will just give you a "CMOS Checksum Error" which basically means data got corrupt in CMOS, and the data (settings) do not match the checksum, thus popping the error message. The #1 reason why this happens is quite simply, a dying battery. I've had this happen in plenty of my PCs, and this is always what has happened, 100% of the time. I've never seen a computer do anything else other than pop the checksum error. Maybe if you're running really cheap motherboards that don't have a CMOS Checksum? That technology has been around since at least the 90s, or maybe even earlier than that, I've had 486 computers that had CMOS Checksums and they all did the same thing when the battery died. Also, how long a battery lasts also depends on whether or not you use the PC regularly. A PC that is in regular use will last far longer than one that is only booted up once in a month, for two reasons: One, Li-Ion batteries last longer if they aren't discharged as much, and Two, if you keep it charged with constant use, it will never have a chance to discharge and it only needs to keep the CMOS running for a few hours. Lastly, if you leave the surge protector your PC is plugged into on, and you leave your PSU on, your PC is not even using the CMOS Battery at all; the PSU is supplying power to the mainboard even while the computer is not actively running. You may wish to turn the PSU off for about 10 seconds and turn it back on before you boot the computer to make sure you have a fresh cold boot, though.

What i think i experienced with pc's i had (cant recall if it was with cmos battery dying, but i think so) is that its important to set the time correct, am i totally out biking on this or kinda right?

Since 1993 I've only ever had that happen once. It was on a PC my brother had for several years before he gave it to me. I haven't had any others long enough for that to become an issue. If you're constantly upgrading and buying new parts you may never run across this.

Funny enough I was looking at my 2032 batteries yesterday thinking how many things actually use them these days including the CMOS haha. Good info as always

I've had my machine running for 5 years and my CMOS battery still runs sweet as a nut. Battery came free when I bought my motherboard too which was a nice touch.

I have an old computer, it's 18 years old now. The original battery was completely dead when I got it 7 years ago. It didn't even detected the SATA HDD at this state, when it was plugged in it said "hardware initialization failure". It worked with an IDE disk, however. I've replaced the battery, the computer was in everyday use for about 2 years, then it got unplugged for 4 years before I turned it to a retro gaming PC as my modern PC can't run my old favorites. I measured 2.7 Volts on the battery but it still works, the clock was only about 10 minutes behind after 4 years without power and it recognize the SATA HDD as well. Maybe time to replace? I started to have issues with another PC when the battery measured 1.1 Volt. It's always plugged in now so it should't drain too fast.

Thanks for the video, very handy tip to know. Although I never had a pc longer than 5 years but hey you never know like you say some bad quality 3v battery could be dead in under 5 years.

Thanks for the video!

Thanks you so much, was having issues booting my pc. I thought it got to do with ky mobo.

What CPU air cooler model is Britec09 using in this video?

I came here wondering if this might explain why my pc recently started spontaneously restarting (as in as if the reset switch had been pressed), seemingly at random in the last few days, until eventually while I was trying different possible solutions it stopped displaying the motherboard splashscreen at all and is now completely unresponsive. No beeps either, but it never did beep on startup. Clearly based on this it's not the CMOS battery, but since I'm here I thought I would ask for advice anyway. While it was restarting I tried various power setting suggestions in windows, and also disconnected the power and reset switches in case they were responsible. Then when it no longer booted up at all I tried unplugging all non-essential usb devices, reseating the memory and graphics card, and even resetting CMOS. The next thing I will do is get hold of an adaptor to allow me to view my main hard disc from my laptop and at least recover the last few days' worth of work that I did between this failure and my last backup, but before I resort to buying a new motherboard and/or anything else, I would welcome any suggestions. Thanks!

What I always found annoying is that there's no way to replace the CMOS battery, even when it isn't dead, with a new battery without having to re-configure all your settings. So, you either make a habit of replacing it every few years or so and, consequently, re-configure your BIOS, or you just wait for it to die when you didn't plan and be forced to replace within the next days less. I suppose you could leave the computer plugged in as you replace the battery, but it's a risky move.

I didn't know that, would the same happen with laptops too? Cause my omen 17 was only 1 day old technically when I first started using it and it refuse to start up after battery running very low

Interesting I have 2 laptops that just quit booting up I had forgotten about the battery guess I need to check it out now. Thanks

thank you so much for this video, king. i think this is whats causing me trouble

Can a dying battery cause micro stuttering like in games and such? im trying to replace the battery in my ASRock Z390M-ITX/ac Mini ITX it has a weird little connector

with out removing the battery on HWinfo on VBAT is the same ? to read the battery ?

Also if you have RAID configuration that will be lost as well. Good idea keep a copy of configuration on paper. Or screen shoots.

My PC was turning off out of nowhere all of a sudden and one day the PC would refuse to boot. The PC would turn on and the case fans were spinning but the CPU, GPU, and exhaust fans werent. Replaced the CMOS battery and it rebooted a couple times then worked like a charm. Never knew these things could die on you. Been using the same motherboard for about 5 years.

Thanks Brian.

I'm pretty good with computers and I've always thought that a failing CMOS battery would just show the error messages shown in this video. I learned that it isn't true even for fairly recent mobos because a dying CMOS battery caused my PC from turning on in the first place. The mobo is an Asus ROG Maximus VIII with an i7-6700K and is around 7 years old or so. First error that occurred was double booting (PC turns on for several seconds, shuts down, then turns on again during POST) while on XMP. I encountered this problem ages ago and the Asus forums always claim that this is "normal" as part of memory training but I managed to solve this by fiddling with some obscure BIOS setting. I was surprised that the problem returned, but noticed that if I didn't turn off the power to the system completely the double boot didn't occur. After a while, there were times when the system refused to power on and it progressed to the point it wouldn't power on at all no matter how many times I pressed the power button. I tried doing a BIOS flashback twice and it didn't solve the problem. I thought it was a motherboard problem so I started using my laptop instead while searching for a second-hand mobo. After around a week I had decided to try turning on the PC and I was surprised that it did, although it didn't last and refused to turn on again later. At this point I realized that the errors that occurred in the beginning might be from a failing CMOS battery. I removed the battery and tested the voltage with my multimeter which showed a reading below 1 volt. After replaced the 2032 battery all the problems disappeared. To make the long story short, if there's anything weird happening at the POST level always consider the CMOS battery. It took me a long time to figure it out because I always had the notion that PCs should be able to boot even without a CMOS battery, you'd just have to enter the correct BIOS setting every time. Unfortunately this isn't true; it's just surprising that the dead battery = no power on would happen in an upper-tier mobo that isn't very old.

Mine manifested with watchdog and driver blue screens, usually when invoking the LAN driver. BIOS and time were remembered so I didn’t suspect battery at first, old cell read 2.9V idle but caves under load.

hi . can i change the battery with the computer running ? that way the bios won't need to be reset? or is there any other way around resetting the bios with computer off? cheers

didnt even know tthis was a thing!! thanks alot!, do the battery have to be a specific size. or all they all the right size to fit into any motherboad.. my motherbaord is a AsRock B450 Pro4

My 2013 alienware laptop keeps shutting down from "low battery charge" even if the battery level is charged at 90%. Do you think the CMOS battery is the culprit or the main battery just toasted?

Thanks for the information🙏🏻, i just found out that motherboard has a battery 👍🏻

So I have a question I updated my bios and on my monitor it said it got my bios settings to default and I was supposed to change customised it back. Next every time I push to start the pc , it starts then goes off and again on by itself. What issue is that ? Cmos or something else?

my pc wont turn on if plug, it will turn on after about 30mins+ after being plug and after the pc starts the windows time is always being reset, does replacing bios can fix this?

On some laptops, certainly ones I've used, nothing happens. That's because once the CMOS battery dies any power needed is automatically redirected from the laptop's battery. In that case you only discover the CMOS battery is dead once the laptop battery is removed and you run it off mains power only. But even in that niche case, nothing happens except system date and time needs resetting and any custom BIOS settings are lost.

Saved my (computers) life 🙂. Thanks!

I just clicked on this out of curiosity because I didn’t know what a cmos battery was and realized that it’s the likely culprit for my repeated boot errors on my ten year old system. I’d just assumed it was my hard drives conflicting at startup but ironically I get the exact issues listed every time I restart it and I’ve just been going through the bios and exiting out just to bypass it lol.

@Britec09 why would my usb ports not be working on my optiplex 760?

W laptopie Acer Aspire E1-571 nie jest to takie proste bo bateria jest źle umieszczona na płycie głównej. Nie mogę się doprosić kombinacji z klawiatury do resetowania baterii w CMOS.

What if when you press F2 or Del the screen turns black and stays that way? Would the battery dying cause that?

Hi once you reset the Bios by removing the cmos battery do you then have to update the bios again?

If my pc become no signal in the middle of working/running is it also causes by cmos battery? I have checked my vga/hdmi cable, clean my RAM, update my graphic driver, those were not the issue

I plugged in a 970 evo into my hdd cable on my PC (dumb move i know) and now the pc wont even boot bios, could the ssd have somehow shorted my cmos battery?

Is panasonic 2032 good enough

Neglecting CMOS warnings by choosing Continue can cause your Antivurus to block access to certain sites like banking, because the date and time is not correct. A pc that is connected 24/7 to mains power is less likely to have issues. I use a standard lifecycle of three years to replace the battery anyway.

When i pull the plug out of the wall (after turning the switch off), i get an error each time on bootup next time i start the pc (after plugging things in again.) I want to be able to unplug it from wall because of power surges ive tried and there will be more in the future. So will changing the CMOS battery help avoid this error? Or am i just wasting my time and taking EDS risks with changing it?

Sir I have a similar problem coming again " Time of the day not set - pleas run the program" this happens when I start after shut down. Dell G3 1790 core I 7 9th Gen. May I change my CMOS

Hi..I can't access my bios in startup is there anything to do with my CMOS battery?I think my CMOS battery is dead I not replace it yet.

Great topic. 👌

bios and timer resets.Can be usefull if you get a bios passworded board.

My serverboard boots up all the way to the windows startup you could hear the windows startup sound but no display output...could that also be due to CMOS battery?

I recently had an issue where I tried to install a dual boot OS (Linux on Windows) but I had an issue with it during installation and when trying to fix it my PC seemed to have just stopped working. I was able to fix it by removing some RAM but do you think it's the CMOS? I've noticed since I've fixed it my PC still doesn't boot properly. Sometimes it powers up, then off, then up, then off etc. Other times I get rapid beeping and no boot Other times I get power up and some little ticks. I suppose it could be the CMOS?

Without Evan Watching the video. Your clock starts to show the wrong time . For one calendar gets wonky. Stuff starts to slow down or you have issues with accessing the drives kits an allover breakdown of your main board systems . Thank God most of the 2032 battery's are replaceable. Some you have to desolder. Oh your random access memory is linked to the cmos battery. That's if I rember it correctly I grafuated IT school in 03 been a while lol

My PC stopped connect Bluetooth and all wireless setting. It's are happening because I tried to remove it with a fork, since then I've been looking for some other options to fix it... But I'm not quite sure if it it's hardware ou software issue. Help

would it shut my laptop off from seemingly nowhere when gaming in a major game like maybe beamng drive?

This is too much info for me, but thanks for reminding me to change batteries in both mine and my mum's computer!

Is there a way to backup your bios settings? I heard that if you change it within 5 seconds you won't lose the settings. Is that true?

Mine just started freezing during kernel. And sometimes during boot wouldn't detect the ssd. Very vague symptoms.

I have a 9 year old PC (not my main one, I use it as a back up/extra storage) and it is still working fine. Should i assume that it doesn't have a CMOS battery in it at all? As surely it would have died by now if it does.

What if it's just the disks, fan header? Time and bios settings are the same.

This happened to my Dell venue pro 11 and I got tired of resetting the clock and date so I just ended up selling it really cheap. It was a touch screen laptop and I did not feel like opening it up. But there then the date and time it worked perfectly.

Its very useful for me because i faced this problem more time.

Can a dead battery cause the entire pc to not turn on? (I got a old toshiba laptop that i never got bother to try change the battery to see if it would turn back on)

Britec my pc is showing its loading but doesn't do anything its just loading can resetting cmos fix it?

im currenly on a otiplex 3020 that i got from schoo l and everytime i shut it down to turn it back on it says the date and time needs to be set and now ik its the cmos battery i have to replace great video

My parent's computer show a "cmos checksum error or cmos battery loss, default bios config loaded" message after EVERY power outage (then i press F1 to continue and all is dandy), could it be that this battery needs a changing?

Great video Brian, quick question. Recently when I boot up my pc it goes to boot then the power goes off and comes back on a few seconds later and it says the pc was not turned off correctly and have to go into my bios to boot my pc up. Is this a CMOS battery problem in your opinion? Cheers Lee.

Mine is beeping 5 times then the fan starts spinning faster and faster but 5he screen remains black. I've only done very few CMOS battery replacements in the past and I'm not quite sure what I've got going on here?

Had a power surge recently and my computer wasn't turning on, but the motherboard lights were on (PC was plugged in the power outlet). From the get-go I already knew it wasn't the power supply module, so I started thinking the motherboard had been damaged somewhere. If you're having the same symptoms, I'll save you some precious hours of anxiety: try reseating the CMOS battery, because it worked for me.

I started having problems like my CPU running hot and couldn't figure out what was wrong. Later, I noticed the time and date inaccuracies. I replaced mine with a used one because I couldn't find a source for a new one that I knew to be the proper one. I am sometimes hearing a high-frequency/low-frequency beep on startup with this used replacement battery installed. If the situation doesn't change, the next thing I will do is test a "new" unverified battery I have sourced to make sure it has at least 3 volts and then test my "used" replacement to see what voltage it is showing. If the "new" battery has 3 or more volts and the "used" replacement is below 3 volts, I will swap out the current one for the new one.

i have a problem where my pc sometimes boots normally and sometimes it beeps and show the no memory detected what can i do to fix it pls help me and I'm sure it's not the ram i tested it

Does it also causes the BSOD?