So after a few days since setting up my mining rig, testing and tweaking I think I got it stable.
The sweetspot for my card seems to be a little core overclock and a lot of memory overclock and half power.
My mainboard is using 20 Watt and the cards between 65 and 75 Watt.
This will cost me less then €1 per day.
This will generate a nice bit of pocket money.
I made a litte powershell script to gather some data and send it by MQTT to my pimatic setup.
Ander after a few days the expected earnings are positive.