I have an answer guys. I was diging on asrock page and see one note in the end with "*******"
If i think good that's why on my screen I see this...And yes i have custom WT.
When I put cpu underload this vrm2 temp is climbing 1:1 with real CPU temp.
Then i suppose this sensor read waterpump temp.

Do you think I'm correct or i don't understand what this is.