Graphic setup for hybrid GPU/dedicated/auto mode disappear in Bios

[LutinChris]

I have two laptops (one HP zbook 17 g3 and one 17 g4). In the Bios settings of those two laptops (section: Built-in Devices) there was an option to set "Graphics" in "auto", "hybrid" or "discrete mode". I try to install a GPU AMD Radeon Rx 480 MXM in those laptops which function perfectly before, but it fails.

- On the 17 G3, the system boots normally up to Windows 10 desktop but the AMD GPU is undetectable in the hardware manager.

- On the 17 G4, the system boots (I hear a beep after pressing f10 for few seconds, also num lock and Maj touches can be activated or deactivated) but the screen stays firmly black (so black screen on boot).

After I removed the faulty GPU (I supposed there was a problem with it), I noticed that in the Bios (section: Built-in Devices) of those two laptops, the option "Graphics" where I could set "auto", "hybrid" or "discrete" mode disappears completely. 

To solve this problem, I try to upgrade the Bios on the two laptops, then to use HP BCU to force the missing settings to come back. But it didn't work.

Since that event, my ZBook 17 G3 could continue using its MXM Quadro m1000m GPU and functions normally apparently even without the missing settings (The "Graphics" option was set in auto mode during the incident). But the ZBook 17 G4 systematically produces a black screen on boot when I add its native discrete card (MXM Quadro m2200). The 17 G4 boots normally up to Windows desktop when I remove the MXM GPU.

I want to know how I could restore the missing "Graphics'' settings in the Bios of my laptops.

My config :

HP ZBook 17 G3 : 256Go SSD + 2To HDD, 8Go DDR4 RAM, CPU Intel Core i5-6440HQ, HD 530 + Quadro m1000m

HP ZBook 17 G4 : 256Go SSD + 2To HDD, 8Go DDR4 RAM, CPU Xeon E3 1535 v6, HD P630 + Quadro m2200