How To CORRECTLY Clear Your CMOS

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I've seen weird and misleading comments before... but this one was so outlandish! Clearing your CMOS is _super_ simple and doesn't take a rocket scientist to figure out. We'll prove it in this video! Here's how to clear your CMOS - multiple ways!

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[bobbymoss]

You the man for making a video out of this specific issue. I actually learned to clear CMOS with a screwdriver watching one of your videos. For many many years I use the little jumper thing that comes on old mobos and optical drives to clear the CMOS. Your method is so much easier and works as intended.

[eldibs]

In my experience, usually jumping the pins or removing the battery for a second or two does the trick, but it's a good idea to wait the little bit of extra time just to be safe. Not like you can over-reset it, after all.

[j.p.h.]

The commenter was talkin about Gigabyte boards. My Gigabyte Aorus B560i Pro AX manual is saying that always turn off your computer and unplug power cord from the power outlet before clearing the CMOS. And this is how it has been since my first clear CMOS in like 1998. 🤣

[BReal-EC]

You missed a fourth option: You can easily clear your CMOS by dunking your fully powered on PC in the bathtub.

[stephenn]

Pretty sure that user will be deleting their YouTube account after they watch this. Greg always responds with class. One of my favorite channels to follow.

[kiwimonster]

Actually, the CMOS nowadays consists of a NVRAM chip (non-volatile) but motherboard manufacturers kept the shortcut of clearing the cmos by taking out the battery bcz people were/are used to this. But, yes, in the past the chips actually were volatile chips

[JatXoc]

Obviously mobo manufacturers want you to short out pins on your board while power is on that way when you short the wrong pins you get to buy a whole new mobo!!

[rollyapostol]

been building pc's and repairing clients pc's for 20+ years now, i just remove the cmos battery to clear the bios...nothing wrong on how Mr. Salazar fix computers..., watched all of his fix or flop videos...i enjoyed everything and learned a lot from him...😀

[cyfergooey]

That's why I enjoy your content. Your honesty to help others and for free. Keep up the awesome work Mr. Salazar, all of us learn new things on your content. Thank you and everyone that helps you create your show!

[RemyL]

UGH. This is one of the reasons why I cannot be a YouTuber. You have way more patience than me, Greg. I have reset the CMOS hundreds of times over the years, and i always use the "remove CMOS battery" method, and barring some isolated incidents, it works. So i cannot even begin to fathom what that guy was talking about. Thank you Greg and sorry you had to deal with that. Upside, you got some useful content from it lol.

[StefanEtienneTheVerrgeRep]

It is clearly seen that every time you have screwed, you haven't screwed with confidence. In 70% of your videos, you aren't screwing anything at all, as there must be power in the system for the screwing to take place. Without power, when if you attempt to screw, it will screw without confidence. In fact 90% of the screws in your video, are without confidence.

[trainmaster]

Love the video. It was straight and to the point. No three hour video with excessive talking about everything not related to the topic at hand. Great job Greg. Keep 'em coming. You've got my vote.

[Skudderable]

Also worth pointing out that if you do turn your PC on and its clock is wrong chances are that CMOS battery is dead and needs replacing they don't last for ever.

[NetRolllerD]

Just to be clear: What's happening when you do this is that the UEFI firmware on the board runs specific code to clear out the UEFI variable store. The variable store is _not_ battery backed, but rather in NOR flash. Exactly how this can be triggered, and also what gets erased, varies between motherboards - some will fully reinitialize the variable store, others just flag all or some UEFI variables as no longer valid. (Think of the variable store as a small file system inside your BIOS chip.)

Because so many people are familiar with "clearing CMOS" by removing the battery, from back in the days when CMOS was actually a thing, most motherboards (but not all - gamer/enthusiast boards usually will, but OEM and professional boards often not) will trigger an NVRAM reset if an invalid RTC date is detected. This, however, is emulated behavior, and can be quite inconsistent between boards.

Also, motherboard makers really need to start labeling that jumper or button "clear NVRAM" or "reset BIOS settings", depending on what it actually does; calling it "CMOS clear" is ambiguous due to the complexity of the UEFI variable store (e.g. it may or may not fix a boot failure caused by a malformed variable entry, as opposed to just bad overclock settings, depending on how "CMOS clear" was implemented).

[Snafu]

Those who know, *do* .
Those who don't know, try to *teach* .
Lavir heart was in the right place. Its just his brain wasn't.

[watercannonscollaboration]

I’m the filthy casual that removes the CMOS battery because sometimes I’m too lazy to search up where the clear cmos header is. Hopefully that commenter is at least willing to admit they’re wrong after watching this video

[discsv]

Great video! I think we should all thank Lavir for their comment coz I'm not sure we would get a video on CMOS clearing otherwise. I think it looked like something so simple for Greg that making this prob wouldn't cross his mind. I for one am happy to realize I didn't get things wrong with my self-taught understanding of CMOS, and it was nice hearing about volatile memory froma professional :)

[ppal]

This is the gigabyte instruction You may clear CMOS to revoke previous BIOS password. Please turn off power and remove power cord from motherboard before clear CMOS. To clear CMOS, you may follow the instruction below:
If there is a [CMOS_SW] button on motherboard, just press this button to clear CMOS.
If there is a CLR_CMOS (Clearing CMOS Jumper) jumper on the motherboard, you may place a jumper cap to temporarily short the two pins or use a metal object like a screwdriver to touch the two pins for a few seconds. (You may refer to the manual about where CLR_CMOS located.)
If there is no CLR_CMOS jumpers or [CMOS_SW] button on the motherboard, please follow the steps to clear CMOS:
Take out the battery gently and put it aside for about 10 minutes or longer. (Or you can use a metal object to connect the two pins in the battery holder to make them short-circuited.)
Re-insert the battery to the battery holder.
Connect power cord to MB again and turn on power.
After clear CMOS, please press DEL to enter BIOS and select [Load fail-Safe Defaults] or [Load Optimized Defaults] then save changes and reboot the system.

[caphowdy]

Many years ago I upgraded the ram in my PC I had at the time, and I was just learning about the workings of PCs (I had an old Dell before that that I had fitted an old school slave/master HDD configuration, and that was it).
Just like with the Dell, when I fitted this ram I looked it up on the internet first to make sure I was doing things properly, and did exactly the same when I fitted my first graphics card as well.
One of the things that was mentioned was if your PC does not post after fitting the ram, reset the CMOS and the only way they told you how to do it was the final option in this video, remove the battery for about 10 mins. Since then this is how I have done it. I have only had to do it one other time, and that is on my current PC when guess what, I upgraded the ram.
I actually forgot about resetting the CMOS and started panicking, pulling the ram out, reseating my original ram etc. Once I calmed down I did a quick google search on my phone and the first thing that popped up was CMOS .. it all came flooding back and worked perfectly.
I never knew there was a reset button on some boards or about the jumper pins until I started watching your videos.
The fact the whole point of the CMOS is to make sure your bios is saved and stuff like the clock is still running, should tell anyone that the CMOS battery is what is supplying the power to it, and that it does not need external power to run.
If the CMOS needed power to work, then every PC anyone buys or motherboard would not work properly when you buy them, because they have not had power going through them for some time potentially.

[Remmes]

Clearing cmos is cutting power from the battery like you say.. it's also why removing he battery also clears cmos.... I don't know why that person so so confident and decided on calling you out when even plenty of manuals tell you to have the system off.