What is setting BIOS password?

[yky]

Recently, when trying to enter BIOS (an Asus motherboard), I was asked for a password. I have never set a password. Thus, the fact that I was asked for a password is unusual. I shutdown the computer, removed the CMOS battery, waited for a while, then started up the computer and hit "DEL" to enter the BIOS. This time, I was NOT asked for a password. I then boot into Windows 7 and restarted the computer. When trying to enter BIOS during this startup, I WAS asked for a password again.

Summary:

1. remove power cord, remove CMOS battery, put everything back, start the computer - no password request
2. afterwards, boot into Windows 7, restart the computer - BIOS asks for a password.

It seems to me a trojan on the harddisk is setting a BIOS password. Is this a valid interpretation of the above behavior?

I have scanned the harddisk with tdsskiller, rkill, aswmbr, AVG. They found nothing. I have used aswmbr to rewrite the MBR, run "bootrec "/fixboot" or "/fixmbr". The password request persists.

For now, I leave the computer alone. But I am thinking perhaps I should try a low level reformat of the harddisk to see if it can stop the password setting behavior. If I do that, I'll have to reinstall and update the Windows. It'll take many hours. I don't want to do it if I don't have to.

 

[TrainableMan]

I remember an old AMD MOBO I had where the default password was AMD and some may default to 1234. Taking the battery out rarely resets the BIOS on MOBOs any more, normally you have to short across the reset pins on the board.

There is a place in the BIOS (usually one of the last tabs) where you can set a BIOS password (and/or a start-up password) so when you do get in, just set a BIOS password you will remember. I'm 99.9% sure a trojan is not setting your BIOS password but even if it could, having a password there of your own would prevent it from being changed. And no I wouldn't format the computer.

 

[yky]

Thank you for the reply. I'll set a BIOS password and see what happens. Since this is an office PC, I expect everyone to hate me for doing this.

 

[TrainableMan]

A Bios password is only needed when you access the BIOS which should not happen often at all. I'm not suggesting you set a startup/boot password which is required every time you turn on the PC.

 

[yky]

I set a BIOS password. Now, I can enter BIOS. Thanks for the advice. I wonder what'd happen if I clear the BIOS password. Maybe I'll try it if someday I have nothing to do.

 

[TrainableMan]

Try it locked down for a while just to make sure it stays.

The truth is, without a BIOS password, anyone who starts up that computer can enter the BIOS and set a BIOS password or a startup password, so if you own the company and the computers you might want to consider locking down all of them with a BIOS password.