I have the SAME problem, reviews on the internet says that this card thottles easily and that it not get the 1250 Mhz or 1270 Mhz that ASUS promisses on the RX470 website, this card REALLY needs a fix by BIOS or anything, because if we put +50 Power Limit on Wattman it easily throttles.
We need a fix asus!!!