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laptop bios

Posted: Wed May 07, 2008 12:01 pm
by Gixxer
is there a battery or connection that will erase the bios password?

Posted: Wed May 07, 2008 12:18 pm
by Randy
yes you can take the battery out for a day or better to jumper you CMOS, should be in your motherboard manual

Posted: Wed May 07, 2008 1:08 pm
by Gixxer
Randy wrote:yes you can take the battery out for a day or better to jumper you CMOS, should be in your motherboard manual
ugh, no manual.

Posted: Wed May 07, 2008 1:13 pm
by YARDofSTUF
Gixxer wrote:ugh, no manual.
Im sure its somewhere on the net in pdf form.

Posted: Wed May 07, 2008 3:19 pm
by Ken

Posted: Thu May 08, 2008 7:44 am
by The Dude
Easily done in a desktop, not so easy in a laptop. In most laptops the BIOS password is stored in EEProms, electronically erasable proms. Removing the BIOS battery will not erase the password. It's done that way by design to make it hard for someone to get in if your laptop is lost or stolen. There might be a reset jumper but don't count on it. Could be realy hard to find too. Try the backdoor passwords. If you can prove ownership Dell or whoever made the PC may help you reset it or give you a password that works.

Posted: Thu May 08, 2008 10:22 am
by Gixxer
i think if i take the battery out and then short the circuit by placing metal on the two prongs will work.

Posted: Fri May 09, 2008 8:35 am
by The Dude
:eek: What two prongs?

Posted: Mon May 12, 2008 11:13 am
by satyre
The Dude wrote:Easily done in a desktop, not so easy in a laptop. In most laptops the BIOS password is stored in EEProms,....

Isn't all BIOS saved in PROM chip regardless of laptop or desktop motherboard?

Posted: Mon May 12, 2008 11:54 am
by The Dude
satyre wrote:Isn't all BIOS saved in PROM chip regardless of laptop or desktop motherboard?
Yes but the eeproms on a laptop can be different from the eproms on a desktop motherboard.

EEPROM (also written E2PROM and pronounced e-e-prom or simply e-squared), which stands for Electrically Erasable Programmable Read-Only Memory, is a type of non-volatile memory used in computers and other electronic devices to store small amounts of data that must be saved when power is removed, e.g., calibration tables or device configuration.

The key difference is you don't need a battery to maintain the settings in an eeprom. Desktop PC's for the most part use a regular eprom that requires an external voltage to maintain its memory. So if you remove the battery the settings get erased. EEproms require a voltage to be applied to reprogram or erase them. Using them in a laptop negates having to use a bios battery which could end up being a pain to replace. It also makes it hard for someone to bypass your bios password if you loose your laptop. On the flip side if you forget your password or end up with a second hand laptop that you don't know the password for, it can be a real pain in the but to reset it.

Posted: Mon May 12, 2008 6:55 pm
by The Dude
Have been doing more research on this and it turns out some of what I posted above may be incorrect. There is likely still going to be a BIOS battery in a laptop even if it uses eeproms. For one thing to maintain the date and time in the BIOS when the main battery is removed while the laptop is not powered by the power pack. Removing the BIOS battery still won't reset the password though, it will just mess up your date and time because the clock circuit will stop. I'm learning a lot of this as I go along so if somebody notices any other errors in what I posted or has better info let me know. ;)

Posted: Fri May 16, 2008 8:33 pm
by ghettoside
I just tried to fix this on 2 laptops this week. Removal of the bat did not clear the password.

I googled it six ways to sunday earlier this week. Best I came up w/ were backdoor passwords for the models... and of course none of them are the password.

http://www.google.com/search?hl=en&q=backdoor+passwords+for+laptops&btnG=Google+Search

As The Dude said, it is that way by design on laptops.

Dell Inspirion PP01L, and an IBM Thinkpad that I don't have in front of me now (may have even made it's way to the trash already).

IBM laptops have the hardest password to crack, and some have a limit of 5 bad attempts and you're locked out. The fix is to replace the mobo.

Wish I would've bookmarked the sites I got my info from. :(

btw, I gave rep points to The Dude.

Posted: Sat May 17, 2008 6:22 am
by The Dude
lol, I have reps turned off, thanks anyway though. :D Backdoor passwords are permanently set in the BIOS and can't be changed. They won't necessarily match the password you have set but if you enter one of the one(s) stored in that BIOS you should be good to go. Problem is even for say Dell, they likely change from model to model or even BIOS version. You end up with a long list to try using Google to search them out. The techs at Dell would now which one works for that model etc. I hear if you can prove ownership they will help you get in and reset it. Might want to have a look at a program called CmosPwd. CmosPwd is a cmos/bios password recovery tool. You might have to run it from a floppy like you do a bios flash. Looks like it has a kill option but it says DO NOT KILL THE CMOS ON LAPTOPS! Anyway Google it to see, maybe it will bail you out.

Posted: Sat May 17, 2008 7:42 am
by satyre
I think if you can reflash the BIOS that should erase the password, if the password is stored in PROM chip.

Posted: Sat May 17, 2008 8:33 am
by YeOldeStonecat
Removing the regular laptop battery will not do it....there's a CMOS battery you also need to remove....often under the keyboard...or under the cover...next to the touchpad...around that area.

Posted: Sat May 17, 2008 9:27 am
by The Dude
Read the whole thread. :p :D Removing the CMOS battery will not always erase the BIOS password in a laptop. In an E squared prom the password is flashed in much like you flash a new BIOS code in. It doesn't get erased when you remove the battery. Flashing may work if you can boot from a floppy.

Posted: Sat May 17, 2008 8:50 pm
by ghettoside
satyre wrote:I think if you can reflash the BIOS that should erase the password, if the password is stored in PROM chip.
been there, done that. Couldn't flash the dell or the thinkpad, lockout prevented that.

The Dude wrote:Read the whole thread. :p :D Removing the CMOS battery will not always erase the BIOS password in a laptop. In an E squared prom the password is flashed in much like you flash a new BIOS code in. It doesn't get erased when you remove the battery. Flashing may work if you can boot from a floppy.
:nod: :nod: :nod:

how to reset the passwords on an IBM Thinkpad
RT/CMOS RAM has 8 bytes reserved for the power-on password and the check character. The 8 bytes are initialized to hex 00. The microprocessor can access these bytes only during POST. After POST is completed, if a power-on password is installed, the password bytes are locked and cannot be accessed by any program.
How to Reset an IBM ThinkPad Power On Password using Software

If you can boot the IBM ThinkPad, KeyMaker will recover the BIOS password.
btw, I tried that "keymaker" and several others between the dell and the ibm... none of them worked. Can't read floppy or cd when locked out, at least on the dell and thinkpad anyway.

Posted: Sun May 18, 2008 7:41 am
by The Dude
Ya it becomes a real pain when you boot options are set to hard drive only and you are locked out. I suppose you could take the hard drive out, format it, sys it and copy the floppy program to it. Then put it back in the laptop and hope it works.

Posted: Sun May 18, 2008 8:04 am
by ghettoside
The Dude wrote:Ya it becomes a real pain when you boot options are set to hard drive only and you are locked out. I suppose you could take the hard drive out, format it, sys it and copy the floppy program to it. Then put it back in the laptop and hope it works.
That's a good idea.

Posted: Sun May 18, 2008 9:03 am
by TonyT

Posted: Sun May 18, 2008 9:23 am
by ghettoside
No, I haven't tried that one, thnx.

I know it won't work on the IBM, too many attempts to get in. I'll try it on the dell this week, if it works I'll post.

Posted: Sun May 18, 2008 11:43 am
by YeOldeStonecat
The Dude wrote:Read the whole thread. :p :D Removing the CMOS battery will not always erase the BIOS password in a laptop.
Yeah I recall coming across that once...many years ago...I think it was a Toshi Satellite model. We made a custom LPT1 jumper dongle to erase it.

Posted: Sun May 18, 2008 1:16 pm
by ghettoside
YeOldeStonecat wrote:Yeah I recall coming across that once...many years ago...I think it was a Toshi Satellite model. We made a custom LPT1 jumper dongle to erase it.
I saw something to that effect, didn't try it.

fujitsu n3410 bios password lost

Posted: Fri Jun 05, 2009 11:21 pm
by antoinefinch
Don't remove the bios battery from this laptop as it will lock the hard drive and set a bios password.I did it thinking I would erase the bios password. No such luck will try fujitsu monday and see if they have a bypass password and more importantly give it to me! can't boot from cd problem huh? could'nt boot from it in the begining. :cry: would removal of the motherboard help I saw some on internet?how hard would it be to replace the motherboard on a laptop?