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Talking Shop: Lost laptop BIOS passwords present a different challenge

Heres what you need to know to pull the battery that maintains the BIOS settings.


Small components and tiny screws make supporting laptops a challenge. However, if you’ve got to get past a boot-up BIOS password on a laptop computer, you’ll need to get over the heebie-jeebies and perform a little open-case surgery.

In the discussion concerning “Two quick tips for getting past a lost BIOS password,” members debated the best way to clear a boot-up BIOS password on a laptop. In that article, the safest ways to clear the password were to:
  • Locate and change the position of a jumper that will clear the BIOS settings.
  • Unplug the machine and pull the battery that maintains the BIOS settings in RAM.

In this article, we will discuss the next best option to sending your laptop back to the OEM. Here’s what you need to know to pull the battery that maintains the BIOS settings.

Don’t do this at home, kids
While the solution to clearing the BIOS settings on a laptop is nearly identical to clearing the BIOS settings on a desktop computer, there are a few notable differences. These include the following:
  • Laptops crowd the same guts as a desktop computer into a much smaller space, and use seemingly twice as many half-size screws to hold it all together.
  • While motherboards and BIOS chipsets are made by a limited number of makers, laptop computers sometimes have proprietary boards and chips.
  • The batteries that power the BIOS when the machines are off are typically near the BIOS chips on a desktop’s motherboard. The BIOS battery on a laptop can be anywhere.

Even laptop models from the same manufacturer can be designed in such a way that you can’t assume the parts will be in the same relative positions as the other laptop models.

For example, at TechRepublic we use a number of Compaq laptop computers. In most of the models we use, the BIOS battery is accessible underneath the keyboard, which pulls out after releasing three tabs above the number keys.

However, Compaq’s Armada M300 is a very compact model, and the BIOS battery isn’t found in the usual place. You have to look at the bottom of the M300 to locate a round cover that conceals its proprietary battery. The wires are soldered onto the battery, but you can find a connection if you gently snake the wiring harness out of the case.

Other options have been suggested
Along with pulling the battery connection, another suggestion in the previous article was to locate your motherboard manual and see if there were any jumpers that could be used to clear the BIOS settings.

Apparently, this isn’t a viable solution with laptops because the battery is often much easier to get to without major disassembly of the computer. In addition, jumpers are not as common in laptops because of the limited space.

TechRepublic members had a number of suggestions in response to the previous article, including:
  • Using a BIOS password cracking program.
  • Using a CMOS killing program.
  • Using a debug script to temporarily clear the password and allow access to CMOS.
  • Using backdoor passwords for specific BIOS programs.

Unfortunately, the first three suggestions refer to clearing what is called the administrative password, which allows the machine to start but prevents users from entering the CMOS.

Even more problematic for these three suggestions is the boot-up password, often called the user password. Without this password, the machine won’t boot far enough to recognize the A: drive, frustrating any program that depends on booting the computer into DOS.

The backdoor password promises the most help, as long as you can determine the maker of the BIOS. A search on the Internet for BIOS passwords can turn up a number of sites listing potential backdoor passwords. One popular site is Win’s BIOS.

Where’s your battery hiding?
Where do you typically find the BIOS battery in your laptops? How easy is it to remove and replace? Send us a note or post a comment in the discussion below.

 

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