Hey guys, I’ve bought a used HP Laptop 15-ay102nf. The Motherboard number is shown as 81EE in the BIOS Welcome Screen, and have a KabyLake i5-7200U with a Radeon R5 430M. Accidentally, I upgraded the BIOS to it’s latest version which is the F.49 Rev.A.
Now i’m looking for a way to downgrade the BIOS, to a previous version! Please help me out to achieve it!
Here’s how i have done the bios downgrade, in few steps:
We need to download the HP BiosConfigurationUtility (BCU), in order to save our Laptop Data Infos including the S/N and such a thing. We must extract the BCU sp143621.exe file, and copy the BCUsignature64.dll with BiosConfigUtility64.exe to a new folder, i’ve used BCU for that.
Now open command prompt as an admin, change directory to that BCU folder, and use the following to dump the config file of your current bios infos by typing:
BiosConfigUtility64 /GetConfig:“Config”
The GetConfig is for creating the actual Bios config infos.
You should now have a Config file that already have all the BIOS infos of your laptop, well, now download the rollback bios of your choice from HP, simultaniously with a one-step lower version. For example: if we want to downgrade to the F43, then the F42 will be the BIOS to flash on the chip. Extract it by simply running it, and selecting copy, then it should let you choose the directory of your choice. Copy BIOS extracted files into a USB, to use them on the computer that will do the bios flashing using the CH341A.
Now, on the folder containing the binnary bios files, have approximately 5 bin and 5 RSA signature files with the same names respectively, and we want to know which bios file is ours, well!
First, after disassembling the laptop, we need the CH341A programmer, and the clip works just well, as it only needs a proper pins connection, maybe in few attempts and it should be done but carefully. The CH341A must already have the ChipsData updated and the W25Q64SV on the list, if not, google it.
Once the clip connected to the Winbound W25Q64SV chip, connect the power battery charger to the laptop, then read the chip, and it will load the actual BIOS.
Ok, Copy the Bioses folder we just putted on the USB to a location of your choice, and dump your bios by clicking on save, then save it to the folder containing the BIOS files.
Now we must know, what BIOS file from the list, is the right one for our laptop. Well, open the dumped bios with a HEX editor and search for BID, and it will result in BIDXXXXX. The caracters on the right of the BID are the name of that bin file you have to choose to downgrade your BIOS, and you always have to choose the same name everytime you want to downgrade your laptop.
Now that we have successfully known, our bios name, we can begin erasing the chip, then selecting our Bios file from the folder for downgrade which is for that example the F42, and click program. Wait until it verify the content successfully and remove the clip from the chip.
Power on the laptop and wait until it boots to the system (you will find that it is booting with “Manufacture Programming Mode is set to Unlock Mode”, and the laptop infos on the BIOS has disapeared).
Now open command prompt again as an Admin, change directory to the BCU folder again, and now, use the following, to set the config file previously created by the soft, into your current bios infos by typing:
BiosConfigUtility64 /SetConfig:“Config”
The SetConfig is for flashing the User Bios config infos file previously created
Now all you need to do is to, reflash the bios with the F43 version, which is the one we need as for that example, using the HP Softpaq Software BIOS Assistant, and thats it!
I wish this will be useful for everyone who got the same experience!