How to clear the CMOS

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Svet

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Here are is the basic procedure to clearing your CMOS.

[youtube]http://www.youtube.com/v/rdHH9KrceR0&hl=en_US&fs=1&[/youtube]


It is important to understand that clearing the CMOS will:
-Restore BIOS's default settings.


It is important to understand that clearing the CMOS will not:
-Restore the original BIOS code (will not revert back to the original bios version).

* Old CMOS clearing method *

Important Note: For AMD Ryzen, AM4 platform skip Step 1 and Step 2,
do not remove power, just shutdown the system before Clear the CMOS
Step 1: (Skip this step for AMD Ryzen, AM4 platform)
Disconnect the main AC power by either shutting off the power button on the back of your power supply or simply pulling out the power cable.

Step2: (Skip this step for AMD Ryzen, AM4 platform)
Wait a minute to be sure all the capacitors and coils have discharged.
To be really safe you can press the power button which will drain the capacitors for sure.

Step3:
Move the CMOS jumper to the clear position, this is usually done on MSI boards by moving JBAT1 from it's original 1-2 position to 2-3 position as demonstrated in the photo below.
If you are not sure or have a non MSI board you must find the correct jumper in your motherboard manual.

Step4:
Wait a minute to be sure the CMOS has been cleared.

Step 5:
Return the CMOS jumper to it's original position.

Step6:
Restore power to the system.

<hr>

* New CMOS clearing method *

Important Note: For AMD Ryzen platform skip Step 1 and Step 2,
do not remove power, just shutdown the system before Clear the CMOS
Step 1: (Skip this step for AMD Ryzen, AM4 platform)
Disconnect the main AC power by either shutting off the power button on the back of your power supply or simply pulling out the power cable.

Step2: (Skip this step for AMD Ryzen, AM4 platform)
Wait a minute to be sure all the capacitors and coils have discharged.
To be really safe you can press the power button which will drain the capacitors for sure.

Step3:
Press the clear CMOS button on the back of the I/O panel.

Step4:
Wait a minute to be sure the CMOS has been cleared.

Note: It is also recommended to remove CMOS battery to ensure 100% CMOS clear on Big Bang X & Intel 6x Sandy Bridge MB's. If date/time do not revert to original time of MB manufacture then you didn't get a complete clear CMOS.

Step5:
Restore power to the system.
 
P

penllyn

Guest
Many thanks. Will try this tonight. Let you know how I get on!
 
S

SantaClaw

Guest
:idea:

Also I wold like to add, on the K7N2 Delta, resetting the bios will NOT reset the bus/fsb to default, so if you were unfortunate like me, and overclocked the FSB to high, and the computer refuses to boot, you need to move another jumper, that enables the motherboard's "Safe Mode" :biggrin:.

I belived that my mother board was broken/faulty and was about to RMA it, since I coldnt find a reffrence to this jumper in the manual that shipped out with my board :angryfire: :angryfire: :angryfire:..

After three long days with a dead motherboard, I had done just about everything i could think off..

I only found the solution by chanse when I read a Review of the mother board....

Iv'e later seen others here on the forum with the same problem.

Some actually RAM'ed their motherboard....

This is the J10jumper, wich wil set the fsb to 100 mgz when in safe mode.. short pins 2-3 and "user settings"(default) if you short pins 1-2.

The "safe mode" jumper is placed just behind the USB connectors on the mother board.
 
S

sportster00

Guest
Hello,

i have a suggestion to add to your guidelines for clearing CMOS.
Usually after i update my bios, i would go into bios setup and enable 'clear nvram'
option, it work for me. I wonder if anyone notice this option ?
 
B

Birch

Guest
Why would one want to clear their CMOS?

I was thinking of doing it because I wanted to reset my BIOS back to the factory settings. But it doesn't work that way (so I read from above).
 
G

Gr8DrunkOne

Guest
Just wanted to say thanks for the help given in this post - it worked great for my problem.

Thanks!
 
K

kstatix

Guest
Also I wold like to add, on the K7N2 Delta, resetting the bios will NOT reset the bus/fsb to default, so if you were unfortunate like me, and overclocked the FSB to high, and the computer refuses to boot, you need to move another jumper, that enables the motherboard's  "Safe Mode" .

I belived that my mother board was broken/faulty and was about to RMA it, since I coldnt find a reffrence to this jumper in the manual that shipped out with my board    ..

After three long days with a dead motherboard, I had done just about everything i could think off..

I only found the solution by chanse when I read a Review of the mother board....

Iv'e later seen others here on the forum with the same problem.

Some actually RAM'ed their motherboard....

This is the J10jumper, wich wil set the fsb to 100 mgz when in safe mode.. short pins 2-3 and "user settings"(default) if you short pins 1-2.

The "safe mode" jumper is placed just behind the USB connectors on the mother board.
I'm not quite sure what you mean?  I'm having a problem clearing my CMOS.

I recently replaced my video card and RAM and when I booted up, the monitor wouldn't receive any signal...I currently cannot access my BIOS to make any necessary changes and I wouldn't know what to change anyway.

I've tried numerous times to clear the CMOS and I still can't get the monitor to turn on.
 
S

start

Guest
kstatix said:
I'm not quite sure what you mean? I'm having a problem clearing my CMOS.

I recently replaced my video card and RAM and when I booted up, the monitor wouldn't receive any signal...I currently cannot access my BIOS to make any necessary changes and I wouldn't know what to change anyway.

I've tried numerous times to clear the CMOS and I still can't get the monitor to turn on.
Unfortunately, i got the same problem as you...how can we go?
Anyone can help us?!!!!!!!!!!
 

Stu

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kstatix & start

this is a Good Article, if you have a problem and want help you should both start your own topics in the relevant forums. read the stickies, read Suggestions on posting and getting Better Answers, post full hardware details and full description of your problem.
 

Wonkanoby

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newer nforce 2 boards


[nForce]: ***Starting your K7N2 Delta2 at default settings***
? on: 19 October 2004, 11:54:07 am ?     

--------------------------------------------------------------------------------
As some of you will be aware there is no safe mode jumper J10 on the K7N2 Delta2 series of boards. This has been replaced by the "insert" key method as used by Abit and Epox. To start your board at its default settings following an unsuccessful overclocking attempt you need to do the following using a ps2 keyboard. Turn off your machine and disconnect from the mains or turn off the switch on the back of the power supply. Press the front panel power switch several times to discharge any charge remaining in the power supply capacitors. Reconnect the power by plugging into wall socket or turning on psu power switch. Press and hold down "insert" on the keyboard and press the case front panel power switch. If you are successful it should start the cpu and memory at 100Mhz FSB. If it does press "delete" to reenter the bios to change your settings to known safe settings. Good luck.
 
E

EoceneVoid

Guest
my bios when crazy, it dont show anything on the screen. After several perhaps more than 20 reset it go to a MSDOS like environment and ask for the bios floopy... someone told me that it is the cmos battery that causing this problem
 
S

stifo

Guest
start said:
Unfortunately, i got the same problem as you...how can we go?
Anyone can help us?!!!!!!!!!!
I have the same problem. It shows no signal on boot and later out of range. then windows starts normaly and windows logon screen is the first screen which is displayed.
 
T

Tiresmoke

Guest
Maybe... Post a topic in the proper area with details and specs. This is not an appropriate area to ask most tech questions as this is about info only here.
 
D

dmcomputerguy

Guest
Wonkanoby said:
newer nforce 2 boards


[nForce]: ***Starting your K7N2 Delta2 at default settings***
? on: 19 October 2004, 11:54:07 am ?       

--------------------------------------------------------------------------------
As some of you will be aware there is no safe mode jumper J10 on the K7N2 Delta2 series of boards. This has been replaced by the "insert" key method as used by Abit and Epox. To start your board at its default settings following an unsuccessful overclocking attempt you need to do the following using a ps2 keyboard. Turn off your machine and disconnect from the mains or turn off the switch on the back of the power supply. Press the front panel power switch several times to discharge any charge remaining in the power supply capacitors. Reconnect the power by plugging into wall socket or turning on psu power switch. Press and hold down "insert" on the keyboard and press the case front panel power switch. If you are successful it should start the cpu and memory at 100Mhz FSB. If it does press "delete" to reenter the bios to change your settings to known safe settings. Good luck.
I tried this and it did not work. A moderator (sorry, don't remember who) suggested that I press the key many times instead of holding it down. That worked for me. Try both ways before giving up.

Note that the "psu power switch" that is referred to is the switch on the back of the case, on the power supply. It is NOT the switch on the front of the case. The wording above is completely correct, but still some people have misintrepreted it because they didn't realize there is a switch on the back of most power supplies.

This is an excellect post, it sure saved me. I didn't see anything about this procedure in the manual. Thank you, everyone who helped on this.
 

leej

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on my motherboard the JABT1 is a giant watch battery i have taken this out but made no difference
my board is ms-7364 v 1.1 any ideas on other options
 

Frankenputer

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Read the manual, page 7.

Clear CMOS Jumper: JBAT1
There is a CMOS RAM onboard that has a power supply
from an external battery to keep the data of system
configuration. With the CMOS RAM, the system can
automatically boot OS every time it is turned on. If you want
to clear the system configuration, set the jumper to clear
data.

Important:
You can clear CMOS by shorting 2-3 pin while the system is off. Then return to 1-2 pin
position. Avoid clearing the CMOS while the system is on; it will damage the mainboard.
 

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quando

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Can someone please tell me where I can find the CMOS jumper or the CMOS button on my U100?
 
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