How to Clear the CMOS - Reset the BIOS & Why

Skip to 04:10 to bypass all the talking.

Clearing the CMOS on your motherboard will reset your BIOS settings to their factory defaults. After clearing the CMOS, you'll need to access the BIOS setup utility and reconfigure your hardware settings.

You might need to clear the CMOS for several reasons but usually you'll want to clear the CMOS to help troubleshoot or solve certain PC problems like hardware compatibility issues.

Sometimes you will have to remove the battery to fully clear the settings.

Many modern motherboards are starting to come with a power, reset, and clear cmos button built right into the board. Those are easy and you won't require the steps I showed you here. Just press and hold one of those buttons down, with the machine off but plugged in.

You might need a standard PS2 keyboard instead of a USB keyboard temporarily. After resettingthe BIOS it is not set to use the USB during the boot up. You need the old style keyboard to plug into the purple port on the motherboard. After you get into the BIOS enable the USB ports.

[danieldavidson]

I'm not sure why everyone is flaming this video saying "Get to the point" but for one I liked that you explained "WHY" you might need to clear the CMOS. Other tutorials on the internet explained the "how-to" but haven't explained the why. Johnny ignore the impatient individuals who can't seem to have an attention span for more than 12 minutes.

[richard]

I agree. there is no reason to bash this guy for giving extra details and taking the time to explain why. Pay attention to detail otherwise you are destined for a fuck up. The smallest and most insignificant details in life can have the most catastrophic effects. Excellent video. Very refreshing to find someone willing to take the time to give an in-depth demonstration rather than listening to 10 minutes of dub step music and trying to figure out what they're doing through a bad camera angle.👍👍👍👍

[Tenshotss]

10 years later, as I am typing the comment. The tutorial was still helpful and straight to the point. I was able to fix my motherboard; and get my PC back up and running!

[kellymiller]

Thank you hot stuff! I'm an old woman still trying to deal with all this technology and you have made it easier to learn! You speak plain and your easy on the eyes!! Thank you!

[michaeldevitt]

You’re a life saver. I got a second 8gb ram stick, tried to boot with a dimms set up, no boot. Tried to go back and test each individual ram stick, no boot. Tried running both in simms no boot. Popped the cmos battery out, rebooted and dimms worked great. <3

[gjv]

I had just Overclocked my PC for the very first time (i5 3570K). I thought it wouldn't be a problem because I have a K in my cpu name. I accept the changes in efi and reset PC.

in all of a sudden my PC won't even power on longer then 2 seconds. I tried like 10 times, i almost went full berserk / panic state.

I stumble across this video 10minutes later. I get my nerves togheter, open my case for the very first time. I manage to find this CMOS thingy and do exactly as Mister Johnny Phung tells me to do... 30 seconds later i start my PC and it works...

Thank you Mister Johnny Phung!!!! THANK

[markregan]

You have done very well in your explanation. I thought I had a dead MOBO. I watched several YouTube DIY fixes but none mentioned the CMOS clearing jumper available on most newer boards.
I was about to replace my board when I watched your demo and decided to try it. Well it fixed the problem instantly. Thankyou!

[tangelone]

I would just like to take a moment to thank you for your clear and concise video regarding clearing the CMOS on a motherboard. I just recently resurrected a Dell Optiflex 320 mini desktop computer from almost certain death thanks to your video. Tell your detractors to piss off! Your video was A-1! It solved my problem. By the way I have never in my life performed this procedure and your video literally made the process a lot less daunting and challenging. Thank you again.

[roberta.]

Keep in mind you dont want to leave the jumper in place for more than a few seconds. Usually a flat screw driver works easily and gets the job done. Now in rare cases where you think the mobo is dead and you tried to reset it a few times to no avail, then instead of losing your mind and buying a new board, put the jumper on and leave it in place for a good 30 seconds to one minute! Sometimes after overclocking its stubborn and you fear you bricked the board try that first, if that don't bring it back use a flat screwdriver and jolt it by making several fast contacts. That method actually saved an Asus board for me once and brought it back to life! Well when all the conventional methods have failed thats when you turn to the unconventional methods I have described luck!

[JosieMakeubetter]

Johnny! I loved your presentation. When I began watching, like most I though hmm....where is he taking me, but it was one of those "wait...for...it.." moments. Very informative. You have your IT Pros that know why they are doing what they do, and you have your IT Pros that cannot explain why they do the things they do, but know it's done that way. Thanks Johnny! Glad I watched your video.

[angelalovett]

Awesome video on resetting the Been looking for something like this for a while now. Something that explains it succinctly but with just the right amount of detail, plus it can be applied to just about any motherboard. Love ya work ;) Thank you!

[shaneelle]

Out of all the videos that I watched trying to figure out how to reset the BIOS settings, this video was by far the most helpful to me. I really appreciated the explanation regarding why you might need to reset it. Thank you.

[FeelFreetoEdit]

Excellently explained Jhonny.
Great work I got a no display problem and when I searched on YouTube your video showed up and it helped me a lot. Thanks for creating a video on explaining about clearing the CMOS. Keep Going 👏🏻👏🏻

[stevenmack]

Very good video! Thanks for not just showing how to do it, but to explain WHY people should do it (if needed). Hopefully you have a career that is utilizing your knowledge!

[daetonoclaray]

My goodness, thank you so much. You literally saved my life, I was so scared that I ruined my computer when I overclocked my computer too much but you taught me how to reset the bios. Definitely a sub even tho ur not posting anymore

[georgestephens]

You never watch this video until you need it... I watched it and now I don’t need it :) thank you very much sir

[jameskethan]

I am taking my 220-801 in two days and this was the most consice video I have seen and I have been studying for MONTHS so kudos my friend. You should teach a class! Hopefully I can find more of your videos if they exist and if they don't they should! Thanks

[meiwa]

Dude! You just saved I was on it the whole afternoon. Checking if the power supply was the problem, changing cables, nodging the screwdriver on the pins. Went over tons of forum articles and videos. Then I finally got to this video. Luckily I had an extra jumper. Thank youuuu! I was laugh-crying upon the sight of my BIOS. 😭😂😂🤣🤣🤣😭😭😂😂 God bless you, man! God bless you!

[John]

You literally just saved my new PC! I changed something in Bios, Windows came up with a sad face closed down and would not restart. I couldn't even get the bios to come back up to change it back. I am still having windows issues, but at least the computer is coming back up! Nothing was scarier than that big black screen and no keyboard input meant a thing! Switchingbthe jumper and resetting it did the trick! Thank you again!!

[totylow]

i REALLY REALLY LEARN WHAT I NEED AT THIS VERY MOMENT, I JUST BUILD A PC FOR MY NEPHEW AND I CHANGED THE CPU SO, THE PC DIDNT BOOT AT ALL! AND A FRIEND OF MINE TOLD ME TO RESET THE MOBO, AND THIS VID ACTUALLY SHOW ME HOW TO DO IT RIGHT! THX A LOOOOT MAN! JUST SUB AND LIKE AND SHARE!