DISCLAIMER
The following are various Debug Routines that you can run on your computer to do various tasks. However, some can possibly damage computer components or cause them not to work properly. We are providing these debug routines as a reference. If these cause problems with the computer they are ran on Computer Hope will not be held responsible for your actions. We recommend that only experienced computer users being aware of the potential hazards use the following routines.
When running any of the below routines you are agreeing to the above statement.
The following debug routine will clear CMOS, BIOS, Passwords, Settings, Viruses, and other items residing in the CMOS. During this process you may get returned characters which are an indication that the string has gone in, if you by chance get ERROR ensure that you have typed the line in correctly, if not retype. Ensure that you do not skip any lines, that it is ALL typed in correctly to help prevent problems. Before running this Debug routine also ensure that you have read the above disclaimer.
After typing debug you will get "-" which is were you can begin by typing A and pressing enter.
A <ENTER>
MOV AX,0 <ENTER>
MOV AX,CX <ENTER>
OUT 70,AL <ENTER>
MOV AX,0 <ENTER>
OUT 71,AL <ENTER>
INC CX <ENTER>
CMP CX,100 <ENTER>
JB 103 <ENTER>
INT 20 <ENTER>
<ENTER> Note: Nothing is typed on this line
G <ENTER> By pressing G this will execute the above script, ensure you have read and agree to the above disclaimer.
Q <ENTER>
Then reboot and you will get a Setup Checksum Error. Go into setup, correct all the incorrect values, time, date...
Flashing BIOS via software
If you have access to the computer when it's turned on, you could try one of those programs that remove the password from the BIOS, by invalidating its memory.
However, it might happen you don't have one of those programs when you have access to the computer, so you'd better learn how to do manually what they do. You can reset the BIOS to its default values using the MS-DOS tool DEBUG (type DEBUG at the command prompt. You'd better do it in pure MS-DOS mode, not from a MS-DOS shell window in Windows). Once you are in the debug environment enter the following commands:
AMI/AWARD BIOS
O 70 17
O 71 17
Q
PHOENIX BIOS
O 70 FF
O 71 17
Q
GENERIC
Invalidates CMOS RAM.
Should work on all AT motherboards
(XT motherboards don't have CMOS)
Existem estes dois comandos.
Eu já usei o segundo numa Intel 440BX e numa outra que agora não sei especificar.
Funcionou perfeitamente.
Mas como o disclaimer diz: "Do it at your own risk!"
Espero ter sido útil.