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How do I reset my BIOS/CMOS to defaults?

Let's get to it!
There are two ways to reset your BIOS/CMOS, the first way is to locate the three pins that relate to the BIOS/CMOS clear header. If the jumper is over pins 1 and 2 it represents normal operation. Therefore to clear the BIOS/CMOS one would place the jumper over pins 2 and 3 for about 15 seconds.

Now remember that the BIOS chip is a EEPROM, this means that it will store information so long as it has suffiecient power, from a power source. In this case it is a silver button cell located on the mainboard, usually of size CR2032 3Volts. Once the jumper is placed over pins 2 and 3 for about 15 seconds, quickly place the jumper back to the normal position, which is over pins 1 and 2.

The second way to clear the BIOS/CMOS is to simply remove the BIOS/CMOS silver button cell, for about a minute and then reinstall it in the correct orientation.

Well thats it, now you will be able to boot your system on the defalts settings. Remember to enter the BIOS/CMOS by hitting the approprite key during Power On Self Test. There are many different keys, depends on your computer system. Common ones are Delete another is F12.
Enter the BIOS/CMOS to correct the date and time and to set the boot priority.

Shown below, on the left, the silver button cell of size CR2032, centre, a yellow jumper on the clear BIOS/CMOS header, on the right, the BIOS/CMOS.

All the best!
damnor01

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li m runing window 7 operating system i forget my bios password so help me to install window in my system


First you have to reset your bios password relax , you can do it. It just take time.There are two ways to approach forcing the Bios/CMOS to be reset to its default values: Option #1: Mechanically, by removing all power to the Bios/CMOS thereby forcing it to reset itself to its stored defaults, which include no password or the default password employed by the Bios manufacturer, and Option #2: Using a program to either locate and identify the password and reveal it to you or erasing the password entirely. These are referred to as password by-pass utilities or cracks. Let's look at Option #1 first, and then move on to Option #2 if necessary.Most motherboards manufactured over the last decade or more use a battery to sustain the dynamic Bios/CMOS settings for the motherboards PROM chip. These dynamic settings are those manually set by either the computers manufacturer or you, the user. There are two ways to erase these dynamic settings, by either resetting a jumper on the motherboard itself (referred to as a "clear CMOS" jumper), or by physically remove the power from the computer (disconnecting the power plug) and then removing a battery (used to maintain power to the PROM chip that contains the Bios/CMOS information) from the motherboard.Some, but not all, motherboard manufacturers provide a set of three jumpers on their motherboards that provide you with the ability to clear the Bios/CMOS settings, thereby allowing them to be reset. For the most part this is used when the Bios/CMOS data becomes scrambled and you need to clear the Bios/CMOS in order to return the computer to a functional state. This same procedure, however, can be used to clear passwords from the Bios/CMOS setup. Typically a jumper will be found across pins #1 and #2 as the default position, and by shutting the computer down, unplugging the power cord and then moving the jumper so that it is across pins #2 and #3 will clear the Bios/CMOS settings.But do not forget to put it back at its same pin as before.
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Aug 19, 2011 | Computers & Internet

1 Answer

i want to reset BOIS password for Gigabyte GA EP43 motherboard which has no jumper, i try to remove battery but the problem unsolved~


There is a CLR CMOS jumper on that MB next to the SYS FAN 2 connector by the IDE header

open = no clr
jumped= Clear CMOS

From the manual page 32

Use this jumper to clear the CMOS values (e.g. date information and BIOS configurations) and

reset the CMOS values to factory defaults. To clear the CMOS values, place a jumper cap on the

two pins to temporarily short the two pins or use a metal object like a screwdriver to touch the two

pins for a few seconds.

• Always turn off your computer and unplug the power cord from the power outlet before

clearing the CMOS values.

• After clearing the CMOS values and before turning on your computer, be sure to remove

the jumper cap from the jumper. Failure to do so may cause damage to the motherboard.

• After system restart, go to BIOS Setup to load factory defaults (select Load Optimized

Defaults) or manually configure the BIOS settings (refer to Chapter 2, "BIOS Setup," for

BIOS configurations).

Jul 20, 2011 | Gigabyte GA-EP43-UD3L Motherboard

1 Answer

I have dell CPX H500GT and lost BIOS password


Almost all motherboards contain a jumper that can clear all CMOS settings along with the BIOS password. The location of this jumper varies depending upon the motherboard brand. You should read your motherboard manual to check its location. If you don't have the manual then look for the jumpers near the CMOS battery. Most of the manufacturer label the jumper as CLR, CLEAR, CLEAR CMOS, etc.

When you find the jumper, look carefully. There will be 3 pins and the jumper will be joining the center pin to either left or right pin. What you need to do, is remove the jumper and join the center pin to the opposite pin. e.g. if the jumper joins center pin to left pin, then remove it and join center pin to right pin. Now wait for a few seconds and then again remove the jumper and join the center pin to left pin.

Make sure to turn the PC off before opening the cabinet and resetting the jumper


The most common way that most of us know on how to reset or clear the BIOS password is to physically remove the power from the computer by disconnecting the power plug and then removing a battery for 30 minutes from the motherboard. Another way is to reset the clear CMOS jumper on the motherboard itself. Both of the 2 methods mentioned works because most motherboards use a battery to sustain the BIOS/CMOS settings for the motherboards PROM chip. So by cutting off the battery power, the BIOS/CMOS settings will be erased.

cmos battery Under the keyboard or bottom of laptop - If you are working on a laptop computer the location of the dipswitch (almost never a jumper) can be under the keyboard or on the bottom of the laptop in a compartment such as the memory compartment.

hope this helps

Feb 27, 2011 | Computers & Internet

1 Answer

forgot the password and cannot start my laptop


Almost all motherboards contain a jumper that can clear all CMOS settings along with the BIOS password. The location of this jumper varies depending upon the motherboard brand. You should read your motherboard manual to check its location. If you don't have the manual then look for the jumpers near the CMOS battery. Most of the manufacturer label the jumper as CLR, CLEAR, CLEAR CMOS, etc.

When you find the jumper, look carefully. There will be 3 pins and the jumper will be joining the center pin to either left or right pin. What you need to do, is remove the jumper and join the center pin to the opposite pin. e.g. if the jumper joins center pin to left pin, then remove it and join center pin to right pin. Now wait for a few seconds and then again remove the jumper and join the center pin to left pin.

Make sure to turn the PC off before opening the cabinet and resetting the jumper



Hope this helps


The most common way that most of us know on how to reset or clear the BIOS password is to physically remove the power from the computer by disconnecting the power plug and then removing a battery for 30 minutes from the motherboard. Another way is to reset the clear CMOS jumper on the motherboard itself. Both of the 2 methods mentioned works because most motherboards use a battery to sustain the BIOS/CMOS settings for the motherboards PROM chip. So by cutting off the battery power, the BIOS/CMOS settings will be erased.

hope this helps

Jan 25, 2011 | Computers & Internet

2 Answers

"Reset you're cmos/bios jumper to


HI,
No need to worry. There are many known ways to reset / remove / bypass the password:
  • By removing the CMOS battery
  • By using the motherboard jumper
  • By using MS DOS command
  • By using software
  • By using Backdoor BIOS password
Now I'll try to explain each method one by one:
A. By Removing the CMOS Battery:
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Almost all motherboards use a small coin sized CMOS battery to store all BIOS settings along with the password. To reset the password, unplug the PC, open the cabinet and remove the CMOS battery for approx. 15-30 minutes and then put it back. It'll reset all BIOS settings as well as the password and you'll need to re-enter all settings.
If it fails, then try to remove the battery for at least one hour.

B. By Using the Motherboard Jumper:
Almost all motherboards contain a jumper that can clear all CMOS settings along with the BIOS password. The location of this jumper varies depending upon the motherboard brand. You should read your motherboard manual to check its location. If you don't have the manual then look for the jumpers near the CMOS battery. Most of the manufacturer label the jumper as CLR, CLEAR, CLEAR CMOS, etc.
When you find the jumper, look carefully. There will be 3 pins and the jumper will be joining the center pin to either left or right pin. What you need to do, is remove the jumper and join the center pin to the opposite pin. e.g. if the jumper joins center pin to left pin, then remove it and join center pin to right pin. Now wait for a few seconds and then again remove the jumper and join the center pin to left pin.
Make sure to turn the PC off before opening the cabinet and resetting the jumper.

C. By Using MS DOS Command:
This method works only if you have access to the system when its turned on because this method requires MS DOS. Open Command Prompt from Programs menu and provide following commands one bye one:
debug
o 70 2E
o 71 FF
quit
NOTE: The first character in the above commands is "O" and not the number 0.
After providing the above commands, restart your system and it should reset the CMOS Settings along with the BIOS password.
If you are curious to know how it works? then let me explain the above commands:
In this method we are using the Debug tool of MS DOS. The "O" character present at first in these commands, outputs the values to IO ports. The number 70 and 71 are port numbers which are used to access CMOS memory. By providing FF value we are telling CMOS that there is an invalid checksum and it resets the CMOS settings as well as BIOS password.

Jan 08, 2011 | Intel DG31PR Motherboard

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