You could try to increase voltage of gpu 0 a little bit.
EthDcrMiner64.exe -epool eth-eu1.nanopool.org:9999 -ewal xxxxx -epsw x -mode 1 -ftime 10 -cclock 1200 -mclock 2100,2150,2150,2150,2250,2150 -cvddc 900,875,875,875,875 -mvddc 900,875,875,875,875,875 -gser 2 -tt 65 -tstop 80 -asm 2 -etha 0 -mport 0
Also could be:
Riser problem
Driver problem
Atipatch problem
You should try increase voltage firist...
My rx 580 sapphire 8gb running between 900-925 cvddc and mcddc.