I am not sure if I have understood the underlying concept clearly. I have MSI B450M Pro board and MSI GT710 GPU based graphics card. Windows 10 installed in UEFI Boot mode on an SSD.
I thought to enable Secure Boot in BIOS. However, there’s a dependent option called Advanced Windows OS Configuration (options CSM/UEFI) which needs to be set to choice 'UEFI' before Secure Boot can be enabled. In earlier BIOS versions same setting was called Windows 10 OS (options were 'Other OS/Windows 10') now its options are called CSM/UEFI though.
(This CSM here under OS Config, I believe is not to be confused with Boot mode that is already set to UEFI.) Then it enables GOP. However, under GOP it says ‘Unknown Driver’. Now, Windows 10 boots fine but when I supposedly enter BIOS, all I see is a black screen. ALT CTL DEL works fine as such and system can reboot even from that black screen, which I believe is resting in BIOS. After BIOS reset (Shorting the mobo pins) when this OS Config setting is back to default CSM, boot logo & BIOS are visible again.
I opened a ticket with MSI and they said that my graphics card does not support GOP.
When I run GPU-Z I see that my card is UEFI capable, so why does not it work with GOP (If that's correct interpretation) and how do I know if a GPU can support GOP? Is there some other reason for black BIOS screen when Secure Boot is enabled? Below are some relevant screenshots. I also tried updating Motherboard BIOS to the latest version but nothing changed. It still behaves the same way.
Update - Even before Secure Boot just changing the OS Mode to UEFI under OS Config gives the same result. Black screen at BIOS. I reiterate that this is not OS Boot mode but OS Configuration mode as termed by MSI. Windows 10 is already installed in UEFI Boot Mode. Legacy Boot (also called CSM) is disabled therein. The term CSM & UEFI appears in 2 different places in this BIOS. Once in Boot Mode (CSM + UEFI) and another in advanced OS Config Mode (CSM or UEFI).
