I appreciate your advices, but in that case I'd need a dummy plug or monitor hooked up all the time to be able to apply clock and voltage settings to gpu's. Am I right?

Greetings to all.
I am in doubt about one thing.

Actually I've built a mining rig from the following parts I already have:
Asus A88x-pro - it has 5 pci-e slots
Athlon X4 740
Nvidia gt 610 for giving me just a picture on the screen
2xRx 580 8gb gpu's
All of that driven by Windows 10

Everything works perfectly, but my main problem is that GT 610 taking up two pci-e slots, so I can't add more than one gpu in the future.
I want to replace Athlon x4 with some apu to be able to free up these two pci-e slots in order to add two more gpu's for mining and to use igpu from apu processor just for the screen.

Is it possible to do that without having an issue with drivers that may interfere between APU and Rx 580 cards?