I'll explain a bit:
the bios of HP, made by Insyde, is a set of modules that provide the interface to the operating system between software and firmware of hardware components.
Along with these modules, there are also tables of ACPI:
dsdt, SSDT, ssdt1, sddt2 (and more), APIC, RSDT, UEFI etc.
Different between F1a or F1b is only cosmetic (some bad recognition memory banks that HP has found on particular brands of RAM stick, but obviously not all), at least dsdt is the same! So for OSX, but also for Windows, you do not realize anything!
So do not worry to choose between F1a or F1b, because they are practically the same!
The point, is that this type of bios, manufactured by Insyde is RSA signed, and this means that he possesses an encryption:
if you try to mod the bios, and flashig it, you will get an error because the generated file will not be the same as the original one signed, and installer stop the job!
RSA is impossible to decrypt, because its keys is so long that it has billions of combinations.
Using an old installer (previous to RSA time), you can flash the bios (the one posted by @simconti and me).
Unfortunately, of course, the signature was invalid on a modded bios, and if you try to change several settings (not all) when you save the setting on the CMOS, the bios chip comparing the two signatures, and will produce error: the semi-brick
CMOS is a volatile memory, this means that when you remove the power (disconnecting the "battery button") the bios back to its original state!...... ALWAYS!!!!!!
So my advice, if you put the modded bios amended as follows:
always leaves the battery is disconnected, and if it happens semi-brick , just remove the battery of the laptop and everything is fine! (wait about 10/12 seconds to discharge capacitors).
Semi-brick happens if there is no patch in dsdt, or sometimes if hard reset made by powering down your Lappy holding the power button (but only if system is already freeze)!
On our dsdt is present the patch to prevent the reset of the CMOS!
Flashing bios on Laptop is always dangerous, even with the original bios!! (think happens if you lost power while flashing the bios: disaster!!)
Unlike motherboards Desktop, Notebooks do not have a removable bios (easy to replace), ........the repair will cost 80 Euros on a not official laboratory in Italy.
Do this only at your own risk!!!!
Feedback from me: the bios mod is ok:
semi-brick is not a total brick, is it always recoverable in few seconds!
Consider, this is not a choice for life, you can put original bios when you want!
-You can not change several settings.
-Possible, recoverable semi-brick
-You can put the wifi card you like, even with bluetooth (the model must be compatible with OSX, of course).
-You can turn off the discrete video card, less heat, and battery consumption increases so much (about 3.5 hours Core i7, i5 think more)
Thank you so much for this details explanation
I just want to make sure from you, i am doing the right steps, because i am really freaked out about this:
1- Leaves the battery disconnected (you mean remove the RTC/CMOS battery)
2- Boot regularly to Windows & apply the modded BIOS
3- Boot to bios and change some settings
3- If it happens semi-brick remove the regular 6-cell battery & AC if connected
and wait about 10/12 seconds to discharge capacitors
4- if nothing happens and all went successfully, turns off the laptop and put the RTC/CMOS battery back and boot regularly
Also i would like to ask you, What are the settings that you can't change when you have the modded bios installed?