Have you try to increase voltage to theses 2 cards? In the log the DAG seems to be not created. Only to discard...
All GPU fully functional, tested in various configurations with ethminer, I tried replacing some GPU with R9 390 8GB, same result, only 5 GPUs working
https://pixs.ru/images/2020/11/16/3b694f0760f64b4aa.jpgIt is usefull to see if they are always the same cards that are 0... or if you swap the pci riser to be 0Mhs another position if that 0 goes to that card or stills in the same position... That will let more information.
