First thing I would do is try a different cable, display port or HDMI. High idle power draw has been a thing for a while. I'm not sure how to fix that. The refresh rate issue could be caused by the cable. Some monitors, like the MSI display I had, only support 165hz over Display Port and 144hz over HDMI.
Ryzen 7 7700X, MSI MAG X670E Tomahawk Wifi, Corsair DOMINATOR® TITANIUM RGB 2x16GB DDR5 DRAM 6000MT/s CL30, Sapphire Pulse AMD Radeon RX 7900 XTX, Corsair HX Series™ HX1000, Corsair MP600 PRO NH 4TB