I have the Zotac GT 610 Synergy 1GB graphics card.
The graphics card does not boot through PCI Express.
I’m not experienced in modifying the BIOS, but I tried some changes using AMIBCP 4.55.0070 without success.
I noticed that even after changing the Secure Boot settings, the system still initializes. I think this might be the reason why the graphics card is not starting, as it forces UEFI Boot mode.
Even when using CSM Compatible in Legacy OpROM, the graphics card appears in the BIOS with 0X speed. This might indicate a driver issue or a lack of permission due to Secure Boot (which I suspect is the cause).
Seems that original vbios of this card model from Zotac doesn’t support UEFI boot environment, so it lacks the EFI GOP driver.
I would recommend to update the vbios from TPU, i see some “Unverified ZOTAC” Zotac 610 vbios or “Unverified Generic NVidia” on their database, that supports UEFI
You can also as alternative, try to insert a GOP driver in the current vbios dump with this tool, as long as the ROM IC has enough space.
This is to avoid messing with the mb bios, that has less percentage of succeedingg.
This board supports CSM Legay and UEFI and for sure there’s no “black list” for GPU cards.
Of course all these actions @ your own risk
Good luck.