CMO, MOBO, UEFI vs BIOS

Sherri is a Cat

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This question is purely about hardware and UEFI...

If someone wants to know why I'm asking this question, I'll explain. The 'Why' really isn't relevant.

Way back when, in the days of BIOS, before UEFI there was a very easy way to reset the password to get into the BIOS settings. Removing and replacing the CMO battery had the effect of deleting the need for a password to enter BIOS settings. I'm wondering it it's the same with UEFI.

Does anyone know? I'm going to try it anyway. At the moment, I'm just too tired to dismantle a laptop.
 


We usually call it CMOS.

There's often a jumper on the board to reset the password. Alternatively, removing the CMOS battery is usually effective.

You can try disconnecting the battery and cable in a laptop and then holding the power button down for a minute or longer. Otherwise, it's the CMOS battery which, as I'm sure you know, is buried somewhere within the bowels of said laptop. I haven't seen a trivially accessed CMOS battery in a laptop in like 25 years.
 
Tell us the make and model of that laptop

I remember it is a Lenovo

Model number ?
 
Did you try to re-create BIOS password or this option is gone? Also, if you ever updated BIOS, then see if BIOS version is the same as the last update.
 
....haven't seen a trivially accessed CMOS battery in a laptop in like 25 years.
HUSH!
Golly! That was 25 years ago???

Hold on... I had a laptop in 2006... Well I guess that's close enough.

Am I really that old? I don't know, someone did say I should act like an adult...

And CMOS, I guess just a zero fell off of the hard drive, an 'S' fell off of the battery.
 
Did you try to re-create BIOS password or this option is gone? Also, if you ever updated BIOS, then see if BIOS version is the same as the last update.

This laptop belonged to my ex. I really tried not to be a nag about the dumb things he did, like say, use the same simple and very easy to guess password for every single account he owned... and yes that includes banking. It seems the one single piece of advice he took from me was to lock access to the UEFI settings with a password.
 
Legacy (BIOS) was so easy to play with...reset CMOS by either battery or jumpers...reset system time and boot order was simple.

Last year my Motherboard (Tower) died...now have UEFI and everything changed...not happy.
m1503.gif


I went into the Setup as it's now called...looked around and hit Exit...bring back the BIOS please.
m1511.gif


As for the lost or forgotten password...you could give this a try...
https://www.linux.org/threads/how-t...rd-from-the-live-session-in-linux-mint.45548/

m1212.gif
 
Legacy (BIOS) was so easy to play with...reset CMOS by either battery or jumpers...reset system time and boot order was simple.

Last year my Motherboard (Tower) died...now have UEFI and everything changed...not happy.
m1503.gif


I went into the Setup as it's now called...looked around and hit Exit...bring back the BIOS please.
m1511.gif


As for the lost or forgotten password...you could give this a try...
https://www.linux.org/threads/how-t...rd-from-the-live-session-in-linux-mint.45548/

m1212.gif
I'm not sure if this can be done with every MOBO or not. My tower has an ASUS MOBO. On mine it is possible to go into Legacy Settings from UEFI. It took me forever to figure out how, but I did eventually get in.
 
I'm not sure if this can be done with every MOBO or not. My tower has an ASUS MOBO. On mine it is possible to go into Legacy Settings from UEFI. It took me forever to figure out how, but I did eventually get in.

Unfortunately my Motherboard is UEFI only...so you're lucky. My 12 year old Laptop is Legacy only and so easy to do everything.

Some changes are good like SSDs...HDMI Monitors...larger Flash Drives...Ventoy...portable SSDs..faster internet...Disk Imaging and Cloning...such is life.
m1233.gif
 
That makes me think of all those sensors on cars. I had a Pontiac Fiero. I don't know they were available in Australia or not. If they did and if you're old enough to remember them, you would know that they were notorious for breaking down. At least once a month I was looking at codes to check for problems with the sensors. That Fiero had 12 sensors. I used a paper clip to get those codes.

Today you need a specialized computer to get information from 100's of sensors!
 
Golly! That was 25 years ago???

Laptops have been a thing for a long time.

A long time ago, I saw laptops with the CMOS battery right there under the regular battery. Back then, we had batteries that you could remove. I recall one laptop that actually had its own access panel for the CMOS battery.

There was a lot of experimentation with the formats back then. Things have settled down to the current form factor that 99% of all laptops seem to follow. Then again, for security reasons, you don't really want your CMOS battery to be all that easily accessed.
 
My motherboard is UEFI only. I would have to know the password in order to remove the requirement for the password.
(talk about a chicken and egg problem). But if I don't know the admin passord for the BIOS...

On my motherboard, I can remove the battery, there is a reset button on the motherboard, ( I have to open the case to reach it )
I don't know if that works on all UEFI motherboards, but it works on mine ( MSI ). I have to hold the button down for about 15 seconds. Then put the battery back in. ( Make sure the AC power is disconnected )

The hassle of this, is now I have to reset all my settings, ( default boot device, RAM overclocking profile, secure boot,
TPM, disable on-board audio, etc... )
 
My motherboard is UEFI only

The way to do it isn't obvious in UEFI. I had to do A LOT of research to finally figure out how to do and it took a long time to find it. I don't know if it works for all MOBO's or not. I'm pretty sure I saved the link. I usually do so I can get back to information I found. Especially links for something so hard to find.

I'll look for it later. If I still have it I'll paste it here. It will be a while though because of all the issues I keep running into!
On my motherboard, I can remove the battery, there is a reset button on the motherboard, ( I have to open the case to reach it )
I don't know if that works on all UEFI motherboards, but it works on mine ( MSI ). I have to hold the button down for about 15 seconds. Then put the battery back in. ( Make sure the AC power is disconnected )

The hassle of this, is now I have to reset all my settings, ( default boot device, RAM overclocking profile, secure boot,
TPM, disable on-board audio, etc... )
 
@dos2unix

I found the bookmarks for getting into BIOS. There are a lot of them. Most of them refer to Windows. At that time, I was trying to install Windows XP on a second hard drive. As I recall XP has to be booted in BIOS.I saved a LOT of bookmarks. I'm glancing through them to try to just give you the ones that might help you get into Legacy settings. Some of articles are gone now or refer to Win 11. Windows 10 hadn't been release yet.

Boot to UEFI Mode or Legacy BIOS mode
WinPE: Boot in UEFI or legacy BIOS mode
 

I have had some dual mode motherboard in the past. I think I still have one or two that might support legacy BIOS, but no motherboard I have bought in the last three years or so supports Legacy BIOS at all. As far as I know, there is no such a thing as a X670E (AMD) or Z790 (Intel) chipset motherboard that supports Legacy BIOS. My Dell XPS laptop is the same way. UEFI only. Legacy BIOS is not an Option. There are some motherboards that have something called "CSM", where you can pick a boot device like PXE Boot, or a hard drive, or a USB thumb drive, and have that specific device in "BIOS mode", but the actually mainboard is UEFI only.
 

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