An explanation of whats going on with the laptop

This is the prepatory section where I explain some things about the chip, CMOS, asset and service tags, and passwords; so that you will have a good grasp of the big picture.

Hopefully it will also clear up any thing you have gotten a vague idea about on another website.

All computers have special chips inside them that store information about the computer.

Some of them are manufactured with permanent information that can not be changed (and, as a rule, all have exactly the same information on them; thus not for passwords.) These contain information about the computer model or are part of its functional circuitry.

Another type of chip (the kind we are interested in) is manufactured with a blank information area that can be programmed or filled with information. These chips are commonly used to store settings and passwords; and come in 2 basic sorts: VOLATILE and NON-VOLATILE.

VOLATILE chips use a source of electricity to help them keep their information, such as a battery. They are less expensive and are used to store computer settings, and also passwords on most computers. If one of these chips has a password on it, the battery can be removed and after a time (between 2 seconds to 30 minutes, depending on the chip) the password will be erased.

NON-VOLATILE chips do not need electricity to keep their information, but are more expensive. If there is a password on one of these chips, it can be removed from power for years and still have the password on it. (However this does not mean that it is permanent.) Remember that the information on Non-Volatile chips can be filled with information. This information can also be changed or erased.

If you have read this far you probably own a Dell or similar laptop with a password that is obviously stored in a Non-Volatile chip, or are an employee of a company that makes one. These laptops have most of their setting information stored in Volatile (inexpensive) chips, and their passwords are stored on a tiny Non-Volatile (more expensive) chip.

The chip that Dell uses is called a 24C02 chip.

This is the Chip Type number used to refer to the chip's design in the electronics industry.

The 24C02 is a small, rather common surface mount* dip* chip with 8 leads (or legs), which costs about $5. It measures 4.5 mm long x 3.5 mm wide x 2 mm tall, and stores 256 Bytes (or one quarter of a Kilobyte) of information. It is commonly used in modems, DIMM Memory, and other electronic devices; and in a different shape it is used in many wallet sized "smart cards." * SURFACE MOUNT means that the chip is soldered onto the surface of the printed circuit, instead of having pins sticking through the board. This is the most difficult type of circuitry to solder by hand. * DIP means 'Dual Inline Package'. This means that the chip has 2 rows of leads (or legs) in straight lines running down its sides.

That's the chip we will be dealing with, if you would like to know more about the chip, click here, or read the "Some unnecessary information about the chip." section later on.

The laptop that was used in this demonstration is a Model 630 type PPX. Other laptops may be different from the one shown in the full breakdown demonstration photos.

If a certain laptop does not correspond to any of these diagrams, more information might be found on the web, or, anyone not reading for informational purposes only - could decide to simply "Wing it."

Also, the chip containing the password may be in a different location on some motherboards, but it should be able to be found by reading the numbers on the top of the chip, although a magnifying glass might be necessary. Take out the hdd and use a ac adapter!

Model / Series

Typ

Chip

Clears

Comments

Latitude

XP

?

not tested

no Info

Latitude

XPi

Yes

Yes

The EEPROM chip 24c02 is on the backside of the motherboard behind the PCMCIA slots. Short circuit Pin 3 and 6 wile booting

Latitude

CP

Yes

not tested

no Info

Latitude

CPi

Yes

Yes

You have to solder two smal wires

Latitude

CPiA

Yes

Yes

The Chip is on the top side of motherboard, under MMC2 processor module. You have to solder two smal wires

Latitude

CPx

Yes

Yes

Picture included.

Latitude

CPxJ

Yes

Yes

The Chip is on the top side of motherboard, under MMC2 processor module.

Latitude

CS

?

not tested

the 24C02 chip is located between Neomagic chip and ram slot

Latitude

CSx

Yes

Yes

the 24C02 chip is located between Neomagic chip and ram slot

Latitude

c400

Yes

Yes

Picture included.

Latitude

c500

Yes

Yes

The Chip is on the bottom side of motherboard, under the PCMCIA card slots.

Latitude

c510

Yes

Yes

The Chip is on the bottom side of motherboard, under the PCMCIA card slots.

Latitude

c600

Yes

Yes

The Chip is on the bottom side of motherboard, under the PCMCIA card slots.

Latitude

c610

Yes

Yes

Picture included.

Latitude

c640

Yes

Yes

The Chip is on the bottom of the motherboard just to the left of DIMM 1.

Latitude

c800

Yes

not tested

no Info

Latitude

c810 c840

Yes

Yes

Picture included.

Latitude

L400

Yes

Yes

remove CMOS Battery for 5 minutes.

Latitude

D400

Yes

Yes

Picture included.

Latitude

D410

Yes

Yes

Picture included.

Latitude

D500

Yes

Yes

Picture included.

Latitude

D505 D510

24c04

Yes

Picture included.

Latitude

D600

24u05

Yes

Picture included.

Latitude

D610

24u05/04

Yes

Picture included.

Latitude

D800 D810

Yes

Yes

Picture included.

Latitude

110L X1

Yes

Yes

Picture included.

Inspiron

2650

?

not tested

no Info

Inspiron

510m 600m

Yes

Yes

24c04 eeprom is under a piece of black sheet under the pcmcia socket

Inspiron

3200

Yes

No

A program called KILLCMOS.EXE is reproted to work for this laptop.

Inspiron

3500

24c164

Yes

Picture included.

Inspiron

3800

Yes

Yes

The Chip is on the top side of motherboard, under MMC2 processor module.

Inspiron

4000

Yes

Yes

The Chip is on the bottom side of motherboard, under the PCMCIA card slots.

Inspiron

5100

Yes

Yes

Chip is on the back side of the motherboard, close to the DRAM slots.

Inspiron

7000

24C164

No

no Info

Inspiron

7500

Yes

not tested

no Info

Inspiron

8000

Yes

Yes

The chip is under the CD-ROM

Inspiron

8100 8200

Yes

Yes

Picture included.

Inspiron

8500

24c04N

Yes

Picture included.

Inspiron

8600

Yes

Yes

Picture included.

Inspiron

1100

Yes

Yes

Chip is on the bottom of the board. 24c168 is near the B ram connector

Inspiron

1200 2200

Yes

Yes

Picture included.

XPS Gen2

Inspiron

M170 9300

24C04

Yes

The chip (C24O4N) is located on the bottem of the laptop right next to the two DIMM slots

Now we are informed and ready to begin. Anyone attempting this procedure should have the implements shown in this picture, along with any others they may deem needful or useful.

They may also wish to write down the Service Tag number for later use, as it will be erased.

Laptop - Screwdriver - Paperclip And remember, when using a screwdriver, it's "righty - tightey, lefty - loosey."_

There are a few things that should be addressed before you continue... I will list them quickly here.

Some of these laptops may have an additional password called a "Hard Drive Password." This may not even become evident until the other passwords have been cleared. This password is stored on the hard drive, it does not mean that the laptop can not be used; it just means that the hard drive can not be accessed.

If you are not able to find out what the Hard Drive Password is, you can simply replace it with another Hard Drive, and then reinstall windows. (I'm assuming you choose windows; linux, solaris, or DOS are fine too.)

Also: I do not know how to bypass, circumvent, or clear the hard drive password._

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