system password

If you lose your password, you will have to erase your CMOS memory or use one of the default passwords available.
Some systems allow you to choose when the password is needed to change the CMOS settings, to boot the machine, etc.

For an AMI Bios you can disable or find out the bios password using AMIsetup (a shareware utility) Download from here:

For AWARD BIOS you can use the crack file Download from here:

You could try various backdoor default passwords.
(THESE ARE CASE SENSITIVE).

AWARD :

djonet

AWARD_SW

AWARD?SW

lkwpeter

aLLY

589589

j262

Other Bios

biostar

biosstar

LKWPETER

BIOSTAR

j262

j256

Syxz

Wodj

Ami

Oder
A.M.I.
AMI_SW
AMI?SW

Or crack it with debug

Enter debug at the command prompt (You must have debug.exe on your system.)
After this enter the debug commands as follows.

O70,1E
O71,FF
O70,1F
O71,FF

Or check to see if there is a jumper setting on your board.
Some computers are designed to be un-crackable.

For a much more detailed chip level password page click here
(at your own risk.)
Check the motherbaord manual to reference the location of the CMOS jumper,rest to manual instructions,also you can try taking out the CMOS battery for a few minutesb but not the BIOS congfiguration before removing

It depends on the manufacturer. It is always possible to remove the password if you have access to the motherboard. Even on Dell computers, you have two pins (named PSWD)to short-cut with a jumper to wipe out the password. Sometime, it is simply a matter of removing the battery long enough (there are condensators placed to keep the the BIOS setup memory alife during a simple battery replacement).

Go to the manufacturer website and download the user manual and you'll find the solution.