Hello world!
All I want… is to set primary video card in BIOS. This used to be an easy job, unless you have an AM4 board. It’s a mystery why most of AM4 boards won’t let you pick what video card you want. Here is a list how different boards deal with this issue. Biostar X470GTA does not have any option regarding primary video card and will default to first PCI X16 slot.
I looked into X470GTA BIOS with AMIBCP and there is a hidden section where you can choose between Integrated Graphics and NB PCie slot video, but I’m pretty sure you still can t pick a specific video card, from a specific slot…
(AMIBCP) If I use ROM dumped with AFUWIN - any enabled option won t show up in BIOS.
Here is the BIOS image dumped with Afuwin 
3rd time’s a charm…
OMG! Now it works! I redumped BIOS and fiddled arround with AMIBCP to enable primary video card menu. Then, I simply changed primary card to IGD Graphics (none on Ryzen 3900X…) and now RTX 2070 Super is ignored and primary video is Voodoo 3 PCI mounted on bottom PCI slot. I was convinced that this is not possible. Even Biostar said so:
