HP Elitebook 840 G2

[Tjaytony]

Re: HP Elitebook 840 G2

Hello guys, i have an hp 840 g2 that a customer brought in. it wont detect usb connection. i have troubleshooted the components relating to the usb. everything seems fine. now i realized that it initially detects usb connection then after the cmos reset reboot, it wont detect usb connection anymore.

so i decided to bring the case here, may be its bios error. here is my main and ec dump below.

following up on this, one of the dumps posted here worked and usb connection is workinf fine now. but its showing machine not in commited state, and it takes several seconds to boot up. could anyone work on my own bios main dump/backup.

[hoaca388]

Re: HP Elitebook 840 G2

following up on this, one of the dumps posted here worked and usb connection is workinf fine now. but its showing machine not in commited state, and it takes several seconds to boot up. could anyone work on my own bios main dump/backup.

What is your serial number? The original file you posted is from the HP EliteBook 850 G2 Notebook PC (ENERGY STAR) with serial number: 5CG5400FK2.

[Tjaytony]

Re: HP Elitebook 840 G2

thats a terrible mistake on my end. yes its 850 g2. serial number is 5CG5400FK2

[Tjaytony]

Re: HP Elitebook 840 G2

What is your serial number? The original file you posted is from the HP EliteBook 850 G2 Notebook PC (ENERGY STAR) with serial number: 5CG5400FK2.

I will check 850 g2 forum maybe i could find a dump there. or if you could help fix my own bios dump

[hoaca388]

Re: HP Elitebook 840 G2

I will check 850 g2 forum maybe i could find a dump there. or if you could help fix my own bios dump

Here
https://www.badcaps.net/forum/showpo...38&postcount=5

[toha-1]

Re: HP Elitebook 840 G2

Hello!
Have in hands abandoned:
elitebook 840 g2
sn 5cg6266w84
pcid a3009d510303

bios with password

tried to reset it with hp_unlock tool and rcunlocker - w/o result. lap turns on after battery attached and blinks

chip was desoldered from m/b and read twice, dump attached. Read with ch431 clamp (desoldered, don't have nest for it) with settings 26/26 spi flash, winbond, w25q128fv (same written on bios)

https://drive.google.com/file/d/1JNM...ew?usp=sharing
https://drive.google.com/file/d/1g-i...ew?usp=sharing

[peste]

Re: HP Elitebook 840 G2

Hello!
Have in hands abandoned:
elitebook 840 g2
sn 5cg6266w84
pcid a3009d510303

bios with password

tried to reset it with hp_unlock tool and rcunlocker - w/o result. lap turns on after battery attached and blinks

chip was desoldered from m/b and read twice, dump attached. Read with ch431 clamp (desoldered, don't have nest for it) with settings 26/26 spi flash, winbond, w25q128fv (same written on bios)

https://drive.google.com/file/d/1JNM...ew?usp=sharing
https://drive.google.com/file/d/1g-i...ew?usp=sharing

post the original bios here not on another site..

[toha-1]

Re: HP Elitebook 840 G2

ok but when i am trying to upload it doesn't works

[wolf3d.exe]

Re: HP Elitebook 840 G2

Trying to unlock a BIOS but made a quite a mess here,

First of all I did not disconnected my cmos battery while dumping, dumped files are attached. Also while I was trying to figure it out probably erased the small chip. Now if I want to reprogram it (desoldered) it says verification error. Picture 1 (small chip, 2mb)

If I use latest AsProgrammer 2.0 as stated in this thread for the 16mb chip and when I try to program it with my HPUnlocker unlocked or some of the unlocked roms in this thread, I noticed erasing goes VERY fast. But write verify takes time. And flash succeeds. Picture 2 (16mb chip)

So I have both chips desoldered, I have dumps for two. When I put them back on laptop laptop goes into rebooting loop. No display.

Obviously something wrong here, why I cannot reprogram the small chip with the original dump?

And why I have a problem of with the 16mb chip?

Thanks

[wolf3d.exe]

Re: HP Elitebook 840 G2

My problem is solved. Issue was the lazy soldering job. Also I will attach the image that worked for me. After reprogramming chip log in to bios as a guest user, surprisingly create an admin account, login to that account and delete existing accounts. Also remove the password for the admin. Voila!

Thanks for the original poster for the BIOS also I used Colibri as programmer. Thanks again for the poster of Colibri. It worked without any errors. I will attach that too.

[kreatywny]

Re: HP Elitebook 840 G2

Hello.
I have trouble after trying to remove my password.
I didn't check the original file with the bios save...
And now I have bios with FF's
After all I've got caps & num lock blinks, fan rotates at full speed & the screen is black.
I've tried bios from #153 - it's the same.
Can someone give me a hint what do now?

Patient:
HP 840 G2
BIOS: Winbond 25Q128FVSQ

I was using Neoprogrammer 2.2.0.10 & CH341A 1.4

[peste]

Re: HP Elitebook 840 G2

Hello.
I have trouble after trying to remove my password.
I didn't check the original file with the bios save...
And now I have bios with FF's
After all I've got caps & num lock blinks, fan rotates at full speed & the screen is black.
I've tried bios from #153 - it's the same.
Can someone give me a hint what do now?

Patient:
HP 840 G2
BIOS: Winbond 25Q128FVSQ

I was using Neoprogrammer 2.2.0.10 & CH341A 1.4

Look for a bios on the site according to the motherboard pattern and try it ...

[kreatywny]

Re: HP Elitebook 840 G2

Look for a bios on the site according to the motherboard pattern and try it ...

Thanks for response. I've got another small question, maybe stupid, but I'm a little confused.
Everybody write about motherboard model with 605...-MB-A02 etc. But on sticker on motherboard I've got only CT: PEVE... + sticker on heatpipe (604... ver: a03) + sticker under battery (607... ver: a02) + under SSD (another 607).
I'm guessing there's another sticker, I need to take the case apart to get into it or I'm blind?

[peste]

Re: HP Elitebook 840 G2

Thanks for response. I've got another small question, maybe stupid, but I'm a little confused.
Everybody write about motherboard model with 605...-MB-A02 etc. But on sticker on motherboard I've got only CT: PEVE... + sticker on heatpipe (604... ver: a03) + sticker under battery (607... ver: a02) + under SSD (another 607).
I'm guessing there's another sticker, I need to take the case apart to get into it or I'm blind?

the model of the base plate should be written in white paint on one of the parts of the base plate...it has this shape
6050a2637901-mb-a02

[electrofrankenstein]

Re: HP Elitebook 840 G2

Hi all! I'm trying to flash a modified BIOS. The flash itself succeeds, but when I install the chip in the motherboard and turn on the laptop, the bios (or some service) runs an automatic recovery tool due to "bios corrupt" or the checksum is wrong. As a result, I have an old bios.
1) Can anyone help me avoid or disable the automatic recovery?
2) I suspect I need to flash the second chip on the motherboard as well, the one 2Mb
But how to create and write the right checksum?

HP Elitebook 840 G2 i7-5600
System board: PEVDT00WB9C00G
BIOS M71 v. 01.31

[electrofrankenstein]

Re: HP Elitebook 840 G2

So, as far as I understand, you ended up flashing both chips?

[peste]

Re: HP Elitebook 840 G2

So, as far as I understand, you ended up flashing both chips?

post the original bios, which programmer do you use? how do you know that the bios is the problem?

[Concord2022]

Re: HP Elitebook 840 G2

This works, but shows machine not in committed state

[mberbouch]

Re: HP EliteBook 840 G2 clear password

Try.

Thanks its working.

[Paul.Junge2020]

Re: HP Elitebook 840 G2

Hello. Help is needed. There is HP 80 g2. I'm trying to remove the bios password through the programs - HPUnlocker, RCUnlocker_v_1_0.
But I'm getting flashing white and red light.
Help me please.