Changes made in v11.4 are related only to AMDs or to NVIDIAs too? I am asking because my Nvidia rigs can run without crashed only on v10.6 version. v11 above is a tragedy for Nvidias

For me too. I have tried to use any 11.x version, but all of them have strange hashrate. It is less then in 10.6. So I rolled back again to 10.6 (