HP bios password unlocking

[mr.Data]

Hello,

I tried to unlock a HP EliteBook 820 G2. There were 2 chips on the motherboard so I tried both seperately with the HP unlocker:
https://www.badcaps.net/forum/showth...=bios+unlocker

After I did the first chip the password was still on the bios. After the second chip the laptop didn't work anymore.

I have read something about an ec chip and that this chip is in sync with the bios.

Do I need to desolder both chips and use the HP unlocker on both dumps before soldering them back on?

Could someone please explain a bit about HP laptops with dual chips?

[RethoricalCheese]

Re: HP bios password unlocking

So you did not read the whole topic.

Larger chip contains main bios. For example if there are 25q128 and 25q64 chips, you only need to read and modify the 25q128 chip. Dont touch the smaller one.

For now flash back both your original dumps and check if your laptop still works.

[mr.Data]

Re: HP bios password unlocking

Despite a lot of errors it worked with one of the ZBooks.

I first tried with a EZP2019 but it read empty chip.

Then I tried CH341a but gave errors (although it did work).

Which programmer would you recommend?

[RethoricalCheese]

Re: HP bios password unlocking

I use two programmers but one is expensive and easy to use. The other one is cheap but difficult to setup/use.
1. EasyJtag Plus
2. Raspberry Pi + flashrom

But did you do it like this:
*Remove battery
*Connect charger
*Turn on laptop, click f1, f10 or whatever
*Turn off laptop but DO NOT disconnect charger
*Connect soic clip
*Read and verify
*Unlock
*Write and verify
*Disconnect charger and soic clip
*Reconnect charger and Turn on laptop

For some programmers this method works all the time. For other programmers there might be other methods.

[mr.Data]

Re: HP bios password unlocking

I have used the clip before with a couple of 6570b laptops which did work but I have tried about 10 different with clip but it took me too much time.

Now I just remove BIOS battery, desolder chip and read it with EZP2019 OR CH341a if the EZP does not read it and then I solder it back on.

[goop]

Re: HP bios password unlocking

*Turn on laptop, click f1, f10 or whatever

Why?

*Turn off laptop but DO NOT disconnect charger
*Connect soic clip

Is the chip supposed to be powered even though the laptop's off?