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how i could clear the system password that stored in cmos ?

thanks

turn it off in the bio setup, or clear out the cmos with a jumper on the motherboard (mb specific)...

I'm pretty sure you can't do it in software, that doesnt seem very secure.

Clear CMOS


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...

MadHacker.

bkilgore wrote:turn it off in the bio setup, or clear out the cmos with a jumper on the motherboard (mb specific)...

I'm pretty sure you can't do it in software, that doesnt seem very secure.

It's not very secure. BIOS is just software on chip media rather than disk media. It follows by definition from this that anything that can be done in the BIOS can be done in software. If all else fails, you can take a disassembler to your own BIOS and see exactly how it's being done.

You should also be aware that anything running on your system with I/O priviliges can probably read your BIOS password.

Hi , I could clear the cmos password ( when security option is set on "setup" ) , usong this simple code :

void RTC_ClearCMOS()
{
Byte j, byte;
char * string ;

asm volatile ("cli");

for ( j=0; j<64; j++ )
   if ( !( read_only[j] ) )
// I 've just make status registers read only


   {       
      OutPortByte( CMOS_ADDR, j );   
      OutPortByte( CMOS_DATA, 0 );   
   }

asm volatile ("sti");
}

I tested this code on a real pc and it succeeded .

Cheers