The flat side of the "knob" is almost in this position: _.
That's too high. Look at your other sticks and for a start, set the pot on problem one to the same angle.
Looking at the pot like a clock, the default is for the flat to be *just* past being in line with the long edge of the stick - call it 15-16 minute position. What you describe I would call the 30 min mark.
I run mine with it set to 20-25 min mark and the stick is quite happy at 500MHz pulling 2.8A.
Damn, then I'm actually slightly undervolting it. Now that I think about it, I believe I slightly reduced it until it got unstable to be on the safe side regarding temps and to lower power consumption a bit. Mine runs like this at roughly 300GH/s.