Mixing AMD & Nvidia GPUs isn't really a problem for the HW, it just complicates managing drivers & software.
if he asking these question clearly he dont know about hw problem in temp/memclock/voltage situation can go wrong if he decided to fully copied config from other people
without knowing it, miner from russian and tropical place it will vastly different config beside sillicon lottery, either way hw monitor is the easy way to get stable config in windows