Ok this is strange..I'm just running some benches here with GPU-Z and wattman open. With my frequency percentage at 0% so default clock, my core is locked at 1630mhz. Ive just done 2 solid runs of heaven and the clock has not budged at all from 1630mhz. I can downlock/overclock it which I then see a difference in the reading, so I know the reading is correct ie the reading has not stuck at 1630mhz, but I thought this would throttle. Sitting at 83c (which I'm really not happy with) with a 2500rpm fixed fan speed for the benches.
Just a note, the card does 1700mhz on the clock dropping the voltage control to 1080mv
going to be fun on water this thing