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FIREWALL
02-06-08, 12:17 PM
If I may ask a question to all.

In reseting my cmos the battery is right next to the jumper.

Which do you recommend : Pull the battery do the jumper.

and if jumper please detail how.

Thx Firewall :)
___

I reposted this this from tonshk's thread and again I ask for a STICKY so this good info doesn't get lost and is easier to find.

So I made my own.:yep: :D

Zantham
02-06-08, 04:03 PM
While you can reset your CMOS by removing the battery, using the jumper is the correct way to reset your CMOS. I use the terms BIOS and CMOS in this post interchangeably.

EDIT Feb07: Due to new information (thanks Subman1), in most (all?) motherboards you must also remove the battery when using the CMOS clear jumper to properly reset the CMOS. Shorting the battery terminals like I mention below is not necessary in this case, since this is what happens when you move the jumper to the clear position with the battery removed. I have added the appropriate steps below (2.5 and 3.5). I don't know if this applies to motherboards that have a Clear CMOS button usually located on the back I/O panel (placed there for people that like to clear their CMOS often ie: overclockers, so they don't have to open their case all the time).

** Ensure you remove all static from yourself by either using a grounded anti-static strip, or touching the computer's power supply before touching any other electronic component.

1) Locate your clear CMOS jumper (or BIOS reset). Note that just because it is near your battery doesn't necessarily mean that that is the correct jumper. Reference your motherboard manual to find the correct jumper. Some motherboards also have a jumper to reset the password, this does not reset the rest of your CMOS to default values however. Sometimes you can find instructions right on the motherboard itself indicating what pins are used.

2) Shut down your computer so it turns off. Unplug the power. Note that unplugging the power is very important - many computers still use some power to the motherboard even when powered off. Generally there is an LED somewhere on the motherboard that remains lit even if the system is shut off but still plugged into the wall. After you unplug the power from the wall, often I will press the power button once more to drain the capacitors (it is not unusual for the fans to twitch or even spin for a second when I do this, even with the system disconnected from the wall.) Any LEDs on the motherboard should now be unlit.

edit: 2.5) Locate the battery on your motherboard. Most motherboards take a CR2032 battery that is approximately 3/4 of an inch in diameter (2cm). Very carefully remove the battery from the motherboard (you may need a small thin-bladed screwdriver). Note carefully which way the battery was facing before you remove it... you do not want to put it in backwards!

3) Typically the CMOS reset (may also be called BIOS reset by some) is a 3-pin jumper. The jumper cap will usually, but not always, be on pins 1 and 2. You clear the CMOS by removing the jumper, and placing them on pins 2 and 3 (or 1 and 2, depending where it was to start). Leave it there for 10 seconds minimum. Then remove the jumper and replace it back on the original pins.

edit: 3.5) Replace the battery back into its holder, making certain you have not put it in backwards.

4) Plug in and power up your system. You should get an error that your CMOS or BIOS setting have been changed, or some other similar error message, at this point you go into your computers CMOS settings, and have fun resetting all your configurations. Generally the default BIOS settings are not the optimal settings, and occasionally, particularily in higher-end systems, your computer may not even boot; for example some RAM requires a higher voltage to run and will not run at the default voltages. You must either plug in some other RAM to reprogram your RAM to run at the higher voltage, hopefully you have some lying around, sometimes you can just plug in a single stick and it may boot allowing you to set your voltage back to the required settings. I mention the RAM here as an example since it is the most likely event to occur.

5) Note that resetting your CMOS will not correct a badly flashed BIOS, nor will it fix a corrupted BIOS (in certain circumstances it may), nor will it correct the problem if you flashed your system with an incorrect BIOS. Sometimes your BIOS will get corrupted by a power spike or voltage drop within the motherboard, resetting the BIOS will most often fix this type of problem.

To reset your CMOS by taking out the battery:

** Ensure you remove all static from yourself by either using a grounded anti-static strip, or touching the computer's power supply before touching any other electronic component.

1) Shut down your computer so it turns off. Unplug the power. Note that unplugging the power is very important - many computers still use some power to the motherboard even when powered off. Generally there is an LED somewhere on the motherboard that remains lit even if the system is shut off but still plugged into the wall. After you unplug the power from the wall, often I will press the power button once more to drain the capacitors (it is not unusual for the fans to twitch or even spin for a second when I do this, even with the system disconnected from the wall.) Any LEDs on the motherboard should now be unlit.

2) Locate the battery on your motherboard. Most motherboards take a CR2032 battery that is approximately 3/4 of an inch in diameter (2cm). Very carefully remove the battery from the motherboard (you may need a small thin-bladed screwdriver). Note carefully which way the battery was facing before you remove it... you do not want to put it in backwards!

3) I generally short the motherboards battery terminals with a paperclip or a screw driver. This drains the CMOS capacitor and will reset your CMOS faster. Or if you so choose, you can just leave the computer unplugged, with no battery in it, for 30 mins or more, some computers will reset quite fast, others I've had take over 24 hours before the capacitor finally drained (which is why I choose to just short out the terminals on the motherboard).

4) Replace the battery back into its holder, making certain you have not put it in backwards.

5) Plug in and power up your system. You should get an error that your CMOS or BIOS setting have been changed, or some other similar error message, at this point you go into your computers CMOS settings, and have fun resetting all your configurations. Generally the default BIOS settings are not the optimal settings, and occasionally, particularily in higher-end systems, your computer may not even boot; for example some RAM requires a higher voltage to run and will not run at the default voltages. You must either plug in some other RAM to reprogram your RAM to run at the higher voltage, hopefully you have some lying around, sometimes you can just plug in a single stick and it may boot allowing you to set your voltage back to the required settings. I mention the RAM here as an example since it is the most likely event to occur.

6) Note that resetting your CMOS will not correct a badly flashed BIOS, nor will it fix a corrupted BIOS (in certain circumstances it may), nor will it correct the problem if you flashed your system with an incorrect BIOS. Sometimes your BIOS will get corrupted by a power spike or voltage drop within the motherboard, resetting the BIOS will most often fix this type of problem.

SUBMAN1
02-06-08, 04:36 PM
Just my two cents - it is a bad idea to short the CMOS jumper without removing the battery. It will short your battery too. :D Pulling the battery also will not always accomplish your objective.

The short answer is - do both if you want to restore factory defaults on a particular system.

-S

FIREWALL
02-06-08, 05:01 PM
I thank you both Zanthan and SUBMAN1 for this step by step procedure.:D

I will keep this and print it out. I don't want to lose this valuable info and that is why I want a STICKY. :yep:

Thx Again :up:

Zantham
02-06-08, 06:39 PM
You don't short the battery when you set the jumper to clear CMOS. Otherwise why would they bother putting in a jumper to clear the CMOS if you have to remove the jumper too... especially when removing the battery clears your CMOS irrregardless of what setting your jumper is on? The jumper is the primary way to reset a computer's BIOS, or as seen in many newer computers they just have a momentary contact switch that is effectively the same as using the jumper but a little easier to use (or hit accidently lol).

FIREWALL
02-06-08, 07:06 PM
You don't short the battery when you set the jumper to clear CMOS. Otherwise why would they bother putting in a jumper to clear the CMOS if you have to remove the jumper too... especially when removing the battery clears your CMOS irrregardless of what setting your jumper is on? The jumper is the primary way to reset a computer's BIOS, or as seen in many newer computers they just have a momentary contact switch that is effectively the same as using the jumper but a little easier to use (or hit accidently lol).

I copy that Z.:)

SUBMAN1
02-06-08, 09:44 PM
Granted, you guys may be right in some situations, but not in 'most' situations. Here is an example of where you are wrong:

http://img153.imageshack.us/img153/3096/asuswi1.gif

Hmm. Seems you have to do both here, no?

Not picking on you guys, but my way is 'safe' for all systems.

-S

antikristuseke
02-07-08, 12:49 AM
Just my two cents - it is a bad idea to short the CMOS jumper without removing the battery. It will short your battery too. :D Pulling the battery also will not always accomplish your objective.

The short answer is - do both if you want to restore factory defaults on a particular system.

-S

No it wont, pulling the jumper will take the batter out of the cirquit and puting the jumper into the other position will ground the cmos cirquit. Now if you put the jumper back into its original position the battery will be back in the cirquit and will keep the changes stored by providing the electrical charge nessesary to keep the bits of information stored on the chip.

Edit: seems like this was allready said, should have read before posting, in my defence it is 8am, i ahve been awake for the past 3 days.

sonar732
02-07-08, 06:42 AM
Edit: seems like this was allready said, should have read before posting, in my defence it is 8am, i ahve been awake for the past 3 days.

Stop with the "realism factor" side of playing SHIV. :rotfl::rotfl:

SUBMAN1
02-07-08, 10:18 AM
No it wont, pulling the jumper will take the batter out of the cirquit and puting the jumper into the other position will ground the cmos cirquit. Now if you put the jumper back into its original position the battery will be back in the cirquit and will keep the changes stored by providing the electrical charge nessesary to keep the bits of information stored on the chip.

Edit: seems like this was allready said, should have read before posting, in my defence it is 8am, i ahve been awake for the past 3 days.Did you look at my post above? You must do both. That pic is from a standard ASUS manual. THe reason for pulling the battery is you are shorting the battery when you are shorting the circuit. WHen the jumper is removed, the battery is out of the loop. SHort the circuit and you short everything. Might be a good way to get your battery to fail and leak all over your nice motherboard.

-S

SUBMAN1
02-07-08, 10:53 AM
I forgot to mention here - All you are doing when you switch this jumper is you are crossing wires. think of it like this - you stuff two wires into your wall plug and touch them together instead of making a circuit (well, technically this is a short circuit so it is still a circuit - but you get the idea). This 'shorts' the entire circuit (battery included) and clears the CMOS. Of course, your MB is going to be using DC in this case, but I am trying to get you to visualize it.

Chances of actually causing battery fail is low however, but if you do it enough, you will definetly kill the life of the battery. There is a ever so small chance of overheating and making the battery either leak or blow up though - but it is minimal. You'd have to short it for a while longer than the 10 seconds recommended I'd bet.

The short answer - if you want your battery to last a long time - like the life of the motherboard, remove it before doing this. Overclockers probably need to worry about this more than anyone though.

-S

Zantham
02-07-08, 11:39 AM
Thanks for the clarification Subman. I work with Asus motherboards all the time (and I'm an avid manual-reader lol) and have never noticed that it mentions to use both the jumper and remove the battery to reset the CMOS. I just verified for a few Asus boards around here and they all agree with what you say about removing the battery and doing the jumper.

antikristuseke
02-07-08, 12:08 PM
No it wont, pulling the jumper will take the batter out of the cirquit and puting the jumper into the other position will ground the cmos cirquit. Now if you put the jumper back into its original position the battery will be back in the cirquit and will keep the changes stored by providing the electrical charge nessesary to keep the bits of information stored on the chip.

Edit: seems like this was allready said, should have read before posting, in my defence it is 8am, i ahve been awake for the past 3 days.Did you look at my post above? You must do both. That pic is from a standard ASUS manual. THe reason for pulling the battery is you are shorting the battery when you are shorting the circuit. WHen the jumper is removed, the battery is out of the loop. SHort the circuit and you short everything. Might be a good way to get your battery to fail and leak all over your nice motherboard.

-S

No, you do not short the battery, the battery will be a part of an open cirquit and there is no current flow though it, at all. the Battery will be on a completely diferent cirquit from the rest of the motherboard at that point. The only reason there is a battery at all is to keep some current flowing through the cmos chip when there are power outages and such. removing the battery and the jumper at the same time is redundant, the reason manuals recomend you do that is to make sure that the bios information is reset in all cases, even when something conductive connects the two pins after jumper removal, occasionaly some fine dust can do that, have personal experiences with that. Allso overclocking has be bearing on the battery's life or health in any way, because the cmos chip will allways run at its stock specification, for there to be any chanse of damage to the battery there would need to be a catastrophic failioure of the power citquitry as a whole which would destroy nigh on every other component on the motherboard, leaving the damaged batery to be a non issue.

Kapitan_Phillips
02-07-08, 12:40 PM
My brain hurts. :88)

SUBMAN1
02-07-08, 01:10 PM
No, you do not short the battery, the battery will be a part of an open cirquit and there is no current flow though it, at all. the Battery will be on a completely diferent cirquit from the rest of the motherboard at that point. The only reason there is a battery at all is to keep some current flowing through the cmos chip when there are power outages and such. removing the battery and the jumper at the same time is redundant, the reason manuals recomend you do that is to make sure that the bios information is reset in all cases, even when something conductive connects the two pins after jumper removal, occasionaly some fine dust can do that, have personal experiences with that. Allso overclocking has be bearing on the battery's life or health in any way, because the cmos chip will allways run at its stock specification, for there to be any chanse of damage to the battery there would need to be a catastrophic failioure of the power citquitry as a whole which would destroy nigh on every other component on the motherboard, leaving the damaged batery to be a non issue.Its a loop. Battery is part of that loop. You are shorting that loop that the battery is a part of to keep current flowing if PSU power is not available.

I'm not going to argue with you over it though. Its not that big an issue.

-S

sonar732
02-07-08, 02:00 PM
My brain hurts. :88)

:rotfl::rotfl::rotfl:

FIREWALL
02-07-08, 02:29 PM
Sorry :oops: did a cardinal sin not posting MoBo and specs.



Intel P4 2.4oa GHz 1mb L2 Cach 533 Mhz PGA-478
Gigabyte GA-8IPE1000-G
4GB DDR 400 RAM
NiVidia GeFORCE 7600GT 512 mb ddr2 8x AGP
m
MAXTOR 320 sata hdd x2
ULTRA X-CONNECT2 550 watt
ULTRA XG Quantum case
Septre 22" widescreen 1200:1 2ms 1680x1050

Hope leting everyone know mobo type helps.

antikristuseke
02-07-08, 03:09 PM
SUBMAN, there isnt much to argue, anyway here is what the circuit basicaly would looks like, grossly simplified ofcourse, I should have done this as the first thing, but nevermind that for now.

http://img248.imageshack.us/img248/4953/hopefullythismakessenseff0.jpg

As for what to do for Cmos clear id recomend you just use the jumper method while leaving the batery in place, but it definately wont hurt to remove it, it is however a redundant step.

Edit:If i misspel circuit one more time im going to slap myself silly

SUBMAN1
02-07-08, 04:07 PM
What you're missing is everyones MB design is different. Is ASUS for example is saying that you need to remove the battery, theirs does not follow 'your design'. That is what you're not getting.

-S

antikristuseke
02-07-08, 04:22 PM
Well, i have had Asus motherboards, I have done cmos clear on them, an yes, acording to the manual that is the procedure one should take, BUT, if you do not remove the battery CMOS clear takes place like it should with no damage to the battery. All motherboards do have that power circuitry that way, because it is the simplest, most cost effective way of doing it while providing the reliability nessesary. So far I have experience with several modelsof Abit, ASRock, Asus, DFI, Epox, Gigabyte, Intel and MSI motherboards and all of them have had that same basic circuit for that purpouse.