HDMI-connected display is blank during UEFI boot

[ScottForum]

When booting via/in UEFI mode, my display connected to a discrete graphics card via HDMI is blank, until Windows starts to load. Why is my HDMI-connected display not showing during UEFI boot?

Notes...
a) I have a DP-connected display to the same card and it has a signal during UEFI boot.
b) In the UEFI GOP setup, I have my discrete card/driver indicated and set to HDMI.

Mobo: GIGABYTE Z370 HD3P
Graphics card: Radeon (AMD) RX550 2GB

 

[ko888]

What's the brand and model of the motherboard and the discrete graphics card?

 

[ScottForum]

What's the brand and model of the motherboard and the discrete graphics card?

Mobo: GIGABYTE Z370 HD3P
Graphics card: Radeon (AMD) RX550 2GB

Edited in original post...thanks.

 

[ko888]

It seems that your Radeon RX 550 is treating the DP connector as the primary output port.

Does your graphics card have a DVI-D port? If it does, have you tried using a DVI-D-to-HDMI adapter to see if the DVI-D port is behaving like the graphics card's native HDMI port during boot?

 

[ScottForum]

It seems that your Radeon RX 550 is treating the DP connector as the primary output port.

Does your graphics card have a DVI-D port? If it does, have you tried using a DVI-D-to-HDMI adapter to see if the DVI-D port is behaving like the graphics card's native HDMI port during boot?

You're right...although I don't have a DVI-D adapter, I did test this by simply disconnecting the DP-connected display. W/o the DP-connected display, my HDMI display was immediately visible.

What I do not understand is the UEFI GOP setting (when I have the graphics card/driver identified and HDMI selected)...I thought it's job was to make sure that my primary display during booting is the HDMI?

 

[ko888]

... What I do not understand is the UEFI GOP setting (when I have the graphics card/driver identified and HDMI selected)...I thought it's job was to make sure that my primary display during booting is the HDMI?

Where is this "UEFI GOP setting", that you've mentioned, located? Is it in the motherboard's UEFI Setup?

I've only seen UEFI GOP used in reference to the pre-operating system environment.

 

[ScottForum]

Where is this "UEFI GOP setting", that you've mentioned, located? Is it in the motherboard's UEFI Setup?
I've only seen UEFI GOP used in reference to the pre-operating system environment.

Yeah, the GOP setting is in the mobo setup, and I thought attached peripherals would adhere to those settings...guess not.

As a result, this is not an error/issue, simply a minor inconvenience...one I can certainly live with. Thanks for the input.

 

[ko888]

What motherboard BIOS Version are you using? In Version F6 they had a graphics card compatibility fix.

 

[ScottForum]

What motherboard BIOS Version are you using? In Version F6 they had a graphics card compatibility fix.

I've got F6 installed. In the bios/UEFI GOP setup it clearly shows my graphics card and respective driver. I looked at the site, and my graphics card is supposedly compatible.