Onboard VGA

From CMOS Battery Reset.

Power off system and unplug power cables
Press and hold power button for 30 seconds
Remove CMOS battery
Press and hold power button for 30 seconds, again
Put CMOS battery back, plug system back in, power system back on (or it powers on as you plug it in, because sometimes barebones does that)

Splash screen shows up <1 minute with minimal POST (+1x GPU) installed on Onboard (front VGA port) display.

Switching to PCI-e device display in BIOS

BIOS settings

Power on system while repeatedly striking 'del' key at the 'American Megatrends' splash screen to access BIOS menu
Platform Configuration Tab → Miscellaneous Configuration → Active Video → Set to 'PCIE DEVICE'
Press 'esc' to go back one page → Navigate to 'Save & Exit' tab (keep striking right on the arrow key, it is the last tab that isn't shown unless you nagivate past the last tab)
Select 'Save Changes and Reset'
BEFORE YOU HIT 'YES', see next steps

Physically switching displays

In short, remove the VGA port, and plug in the display to the Graphics Card. Having both plugged in will result in only splash screen on VGA and nothing past that on any other display-capable device installed to the motherboard. EDIT 7/2/21: Having both displays SOMETIMES work.

This motherboard in particular DOES NOT support display auto-switching, meaning if it fails to output proper display through sequential hardware initialization (during POST, detecting display devices and cable to monitor), then it will just never display anything past the splash screen at all; if you missed it, or did this incorrectly, you will need to press+hold the power button for 5 seconds to power off the system and start over by powering the system back on so it can go through POST again.

Hit 'enter' for the 'Yes' to 'Save configuration and reset'
IMMEDIATELY unplug VGA cable and plug in the graphics card display
System will reboot twice (results may vary), 1 time after ~1 minute, and then again ~20 seconds after the 1st reboot, then it will display through PCI-e device
Keep striking the 'del' key to get to BIOS menu

From the VGA display if you have 'PCIe Devices' set as primary video

If you plug in VGA cable, AND the 'Primary Video' setting in BIOS is set to use 'PCIe Device', then you will be met with this 'DXE-Setup Input Wait' screen with 'AB' code on the bottom-right. This is consistent, so no-display with any other code might indiciate an issue with BIOS or motherboard.

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