HP Elitebook 840 G5 Black Screen

[hoaca388]

Hi, I have a 840 G5 that had black screen and fan speed max, I've found a bios files 16 and 32 that works, but after to flash I have a security error on start "HP EndPoint Security Controller Problem"

, I've tried to resolve with hp dmi tool but it don't works. Now I have a wrong serial and I think also wrong security o something like wrong mac address. I've attached the original files, can someone help me to solve this issue?


Serial Number : 5CG9154WPG
Product Number : 2FA66AV
Description : HP EliteBook 840/846 G5

BID = 17WWCSCT601#SABZ#DABZ
FEATUREBYTE = 3X476J6S6b7B7H7M7Q7W7m7saBaEapaqauawbUbhcAdUdpdqhKhkjh.F5

VVV

[lzeta]

VVV

Thank you so much but with this original file again black screen and fan max speed. Can you adjust the working one with correct DMI info? Resolve it also security error on start?

[lzeta]

I forgot the mac
MAC 1 : 9C7BEF697AAE
MAC 2 : X9C7BEF697AB0

[lzeta]

Please can someone help me?

[lzeta]

bump

This is the last bios file I've installed, now all works fine but "HP EndPoint Security Controller Problem" and DMI info are not the original

[hoaca388]

bump

This is the last bios file I've installed, now all works fine but "HP EndPoint Security Controller Problem" and DMI info are not the original

File is corrupted.

[lzeta]

File is corrupted.

Tahnks, I've read an save it from working notebook, using tl866ii plus with this adapter:

[nesredin]

how to solve "HP EndPoint Security Controller Problem" 840 g5

[eliberate]

Re: HP Elitebook 840 G5 Black Screen

So I have 20 of these things my wife got and decided to give them to kids... unfortunately, all 20 are bios locked

I have an RT809F programmer and extracted the bios 32mb bios.

I used the HP Bios unlock tool and then wrote back the bios but now the caps lock light blinks then the fan runs high.

I wrote back the original bios and the same issue

Question

1. Do I need to read and reprogram both 16mb and 32mb chips? My understanding from reading all I need to do is just the 32mb
   If all I have to do is just the 32mb why did it fail?
2. Since I have 20 840 g5 is there generic firmware(s) I can use to just write to all and re-input serial numbers etc?
   If so are there detailed steps for this?
   

Hi, did you solve this? i have the same problem

[MR KUJO]

Hi, I need help with my HP 840 G5 BIOS. When I turn on the laptop, the Caps Lock and Num Lock keys blink five times simultaneously and then stop. The fan starts spinning quickly, but the screen stays black. Below is the information for the old BIOS file:
- Product ID: 4QQ31UC#AKB
- Serial Number: 5CG83935H8.

[hoaca388]

Hi, I need help with my HP 840 G5 BIOS. When I turn on the laptop, the Caps Lock and Num Lock keys blink five times simultaneously and then stop. The fan starts spinning quickly, but the screen stays black. Below is the information for the old BIOS file:
- Product ID: 4QQ31UC#AKB
- Serial Number: 5CG83935H8.

HP EliteBook 840 G5 Notebook PC