[Help] InsydeH2O BIOS unlocked without mod, possible NVRAM variable unlock?

Forgive me if I sound completely clueless or downright stupid here, I’m relatively new to BIOS mods.

I currently have an HP Envy 15t-k200 CTO (Haswell CPU) laptop that I’ve been using with OpenCore to run macOS. The BIOS version is InsydeH2O F.57 released by HP back in 2018. I have made previous efforts to educate myself on how to mod the BIOS as I could use the advanced options (especially with OpenCore) but decided it would be out of my league as it’s an RSA signed BIOS and the setup variables seemed to be locked (ie: setup_var, RU have no effect).

A few months ago I updated to OpenCore 0.6.2, and then again to 0.6.3 (Important) and after a few reboots I decided to enter the BIOS to change a few settings. When I entered the BIOS I noticed all the Forms were available, and all advanced options could be accessed and changed. Any changes I would make would also stay. This stayed the case until recently, after updating to 0.6.5 and doing a clean install of Big Sur I noticed the BIOS options were once again limited.

I think OpenCore may have had a hand to play in this, at least the versions 0.6.2-0.6.3 as there was a bug in the bootstrap that caused some people to experience BIOS issues. After 0.6.4 they changed the bootstrap and this bug is no longer present. It’s also worth noting that this bug seemed to affect not only Haswell systems, but InsydeH2O BIOS firmware images as well.

Bugtracker issue: https://github.com/acidanthera/bugtracker/issues/1222
Solution: https://github.com/acidanthera/bugtracke…mment-739241310

Unfortunately I never dumped the UEFI variables or even backed up the BIOS image. I have attempted to replicate this by downgrading both OC and macOS but have been unsuccessful in getting the same results. It’s possible that this occurs after a certain number of reboots but I honestly can’t even speculate on that.

Is it possible that certain NVRAM variables or boot#### entries could change the way the setup utility is accessed? If so, could this be replicated?

It’s worth mentioning that I have never attempted to flash a mod BIOS with this PC. Also when viewing the image with H2OUVE all the settings are available and disabling suppression/grey-out doesn’t show any extra options. Actually accessing the BIOS only shows 4 out of the 8 forms. Also for whatever reason this PC can downgrade to F.56 through the default setup utility on windows, but no lower (not officially supposed to be able to downgrade, but can for F.57 → F.56)

Supplemental Info:

Default visible BIOS forms:

Main - https://imgur.com/iAxagzL

Security - https://imgur.com/d8xVMTg

System Configuration - https://imgur.com/CxUlOyI

Exit - N/A (Just Save, Discard and Load Defaults)

Hidden BIOS forms:

Main #2 - https://imgur.com/BUHlSMA

Advanced - https://imgur.com/LphEdju

Security #2 - https://imgur.com/wAvND8x

Power - https://imgur.com/Wd9bjMR

I’ll attach the extracted Setup IFR and BIOS bin file, though if there’s any issue this can be obtained from sp92961.exe (platform is 2290(02291.bin))

Section_PE32_image_DriverSampleDxe_SetupUtility.txt (657 KB)

02291.bin.zip (3.75 MB)