BIOS passwordsare used to add some extra security to computers. You can either set a passwordto prevent access to BIOS settings or to prevent PC from booting.
But sometimesthis extra security might become a pain when you forget the BIOS password orsomeone changes your system BIOS password intentionally.
But there is noneed to worry. There are many known ways to reset / remove / bypass thepassword:
· By removing CMOS battery
· By using motherboard jumper
· By using MS DOS command
· By using software
· By using Backdoor BIOS password
Now I'll try to explain each methodone by one:
By Removing CMOS Battery:
Almost allmotherboards use a small coin d CMOS battery to store all BIOS settingsalong with the password. To reset the password, unplug the PC, open the cabinetand remove the CMOS battery for approx. 15-30
minutes and thenput it back. It'll reset all BIOS settings as well as the password and you'llneed to re-enter all settings.
If it fails,then try to remove the battery for at least one hour.
By Using MotherboardJumper:
Almost allmotherboards contain a jumper that can clear all CMOS settings along with theBIOS password. The location of this jumper varies depending upon themotherboard brand. You should read your motherboard manual to check itslocation. If you don't have the manual then look for the jumpers near the CMOSbattery. Most of the manufacturer label the jumper as CLR, CLEAR, CLEAR CMOS,etc.
When you findthe jumper, look carefully. There will be 3 pins and the jumper will be joiningthe center pin to either left or right pin. What you need to do, is remove thejumper and join the center pin to the opposite pin. e.g. if the jumper joinscenter pin to left pin, then remove it and join center pin to right pin. Nowwait for a few seconds and then again remove the jumper and join the center pinto left pin.
Make sure toturn the PC off before opening the cabinet and resetting the jumper.
By UsingMS DOS Command:
This methodworks only if you have access to the system when its turned on because thismethod requires MS DOS. Open Command Prompt
from Programs menuand provide following commands one bye one:
o 70 2E
o 71 FF
The first character in the above commands is English alphabet "o
"and not the number 0
After providing the above commands, restart your systemand it should reset the CMOS Settings along with the BIOS password.
If you arecurious to know how it works? then let me explain the above commands:
In this method we are using theDebug tool of MS DOS. The "o
" character present atfirst in these commands, outputs the values to IO ports. The number 70
are port numbers which are used to access CMOS memory.By providing FF
value we are telling CMOS that there is aninvalid checksum and it resets the CMOS settings as well as BIOS password.
There are a few software which canalso reset CMOS settings or BIOS password or both within a few clicks. But asstated above you should have access to a system which is turned on and shouldhave access to MS DOS or MS Windows:
By Using Backdoor BIOSPassword:
Some BIOSmanufacturer put a backdoor password in BIOS which always works irrespective ofwhat password you have set in BIOS. Its a master password which is used fortesting and troubleshooting purposes.
AMI BIOS Passwords:
AWARD BIOS Passwords:
shift + syxz
Misc Common Passwords:
Other Manufacturer BIOSPasswords:
- spoomlPackard Bell
- ToshibaVOBIS & IBM
All thesepasswords are case-sensitive and are changed from time to time bymanufacturers.