Thank you all for the help, at the moment I'm trying to follow what
@pastrychef suggested.
Yes
My primary display was IGPU, I switched to PCIe Slot 1 (PCIe x16) but the display didn't work. Then, I moved the GT 710 to Slot 2 (PCIe x8) and the system now boot successfully with the PEG being detected properly by MacOS. No more graphical glitches at this point, but as soon as I plug the second monitor to the IGPU HDMI port the OS freezes and reboots. If this second HDMI is already plugged when the PC turns on, the OS freezes at login screen and I have to reboot manually.
If I look at the system info, under "Graphics/Display" it just shows the NVIDIA GT 710 and no longer the Intel UHD 630.