RX 580 running at 900 MHz or more - clock too high

[rajovo]

RX 580 on X570-p, 10.15.6 on OC 0.5.9. According to iStatMenus, RX 580 idles at roughly 900 MHz and takes 135W, which is ridiculously high. In Windows 10, it idles at 300 MHz.

Anything I can do? Thanks!