BIOS Downgrade Needed - HP Spectre X360

[Joe238]

I have a Spectre X360 (Z4Z38UA#ABA) i7-8550u, 16gb ram, running win 10 ver 2004. It is a fresh windows install. I need to downgrade the bios to F34RevA or earlier as available on https://support.hp.com/us-en/drivers/selfservice/hp-spectre-15-bl100-x360-convertible-pc/16779592/mo... I need to downgrade due to severe impact on system performance and lag. I've got about a 60% performance hit, lots of lag, especially my VMs. Programs that were an instant launch before are now taking 30 seconds... I have never updated the bios in this laptop since I originally bought the machine (fall 2017) and I ran the "HP Support Assistant" and it automatically suggested an update so I ran it. I went from "F.20 Rev.A" to "F.42 Rev.A". I noticed the system became unusable, tried to downgrade to the original bios but it wouldn't let me. I figured maybe it was time for a fresh win 10 install. Didn't help.

When I execute the F34RevA bios "sp85047.exe" in windows, there are 3 options:

(Option 1) the  "update" option is grayed out. It (and prior versions) says that "This is an older version of BIOS which is not compatible with your system configuration". I do know it was compatible because I was just running it though prior to the update.

(Option 2) "Create Recovery USB Flash Drive". When I setup the usb recovery disk and boot from it I get the error "The selected boot device failed. Press <enter> to continue" but it never works. I do have secure boot disabled. I tried manually launching the EFI file within the boot usb. This works but it says "unable to open BIOS image file". I've tried all the various EFI files on the boot disk. None of them successfully enable me to flash F34revA or prior.

(Option 3) "Copy BIOS image to any file location". This is where the .bin & .sig files are manually extracted. For this method, I've used the latest version of the HP Diagnostic Tools to try and flash F34RevA but it will say that it cannot read the signature file. I have managed to downgrade to F39RevA using this method, but the extreme slowdown and lagginess persist. There is some noticeable improvement though. I've tried every single bios prior to F39RevA but it won't let me flash them. I can successfully flash bioses after F39RevA but not before. So, I've successfully downgraded to F39RevA but I need to go lower, back to the original bios before this mess started that rendered the laptop unusable (especially my VMs)

Any help would be greatly appreciated. Even if someone knows that it is impossible to downgrade past F39RevA that would be helpful to know. If there are also any 3rd party "flash at your own risk" tools that I could use, I'm willing to try anything.

Thanks for your help!!  🙂

Update: 6/16/2021 --> No solution offered yet or discovered on my own.

[Echo_Lake]

@Joe238

Thank you for posting on HP Support Community.
 

Don't worry as I'll be glad to help, I have a few troubleshooting steps we could try to fix the issue:  

The HP Cloud Recovery Tool allows you to download recovery software to a USB drive. You can use the downloaded recovery image file in order to install the Windows operating system. 

• Click here: https://support.hp.com/in-en/document/c04758961#AbT3to perform System Recovery (Windows 10) 
• Click here: https://support.hp.com/in-en/document/c06162205 to Use the HP Cloud Recovery Tool (Windows 10)

Hope this helps! Keep me posted for further assistance.
Please click “Accept as Solution” if you feel my post solved your issue, it will help others find the solution.

[Joe238]

I am not having a problem installing/reinstalling Win 10. I've already freshly reinstalled windows as an attempt to fix my problem and that didn't work. My problem is that I want to flash a  BIOS version F34RevA or earlier.

[Echo_Lake]

@Joe238

Thank you for posting back.

Let's try this method to rollback BIOS:

1. Firstly,  remove the hard drive from the computer.
2. Once the hard drive is removed turn on the computer without the hard drive- While booting as the computer doesn’t detect a hard drive, so it’ll automatically roll back to the previous bios.
3. Put the HDD back in and turn it ON. It might give an error about improper shutdown. Just click continue and it should boot to windows.

Hope this helps! Keep me posted for further assistance.
Please click “Accept as Solution” if you feel my post solved your issue, it will help others find the solution.

[Joe238]

Unfortunately this does not help because as mentioned in the post the previous version is not the version I'm trying to rollback to. In my case the prior version is not  F34RevA or earlier. As mentioned in the original post, I downgraded from F42RevA to  F39RevA in my various attempts to rollback. Thus the prior version is F42RevA.

[Echo_Lake]

@Joe238

Thank you for posting back.

I appreciate your efforts to try and resolve the issue. This sounds like hardware related issue with the computer and in order to fix this issue, your computer needs to be serviced.  As we have limited support boundaries in the support community as of now. 

I would request you to reach out to our Support and our Support Engineers should be able to check the available service options in order to diagnose the computer physically.  HP Support can be reached by clicking on the following link:  www.hp.com/contacthp/

Please feel free to contact us here anytime you need any further assistance. Please click “Accept as Solution” if you feel my post solved your issue, it will help others find the solution.

[Joe238]

Based on googling, the best answer I can find is that HP has locked the bios after the security vulnerability of Meltdown & Spectre (not to be confused with the HP spectre brand) had been patched. It is not a hardware failure issue but a software bios issue. This is my best guess on what is really going on. Does anyone know of any workarounds or flash at your own risk tools to downgrade the bios?

[Echo_Lake]

@Joe238

Thank you for posting back.
Apologize for inconvenience caused.

I would request you to contact our Support and our Support Engineers should be able to Remote into your computer and sort this out. HP Support can be reached by clicking on the following link: www.hp.com/contacthp/

[Joe238]

Hey Echo_Lake, I think you accidently posted again. I've responded above why this will not work.

[Echo_Lake]

@Joe238

Thank you for posting back.

As we performed relevant troubleshooting steps and the issue persists, 

I would request you to reach out to our Support and our Support Engineers should be able to check the available service options in order to diagnose the computer physically.  HP Support can be reached by clicking on the following link:  www.hp.com/contacthp/​​​​​​​
 

Please feel free to contact us here anytime you need any further assistance. Please click “Accept as Solution” if you feel my post solved your issue, it will help others find the solution.