I have almost the exact same setup only I have the KF of the CPU. Otherwise same. This is a fantastic Combo. The MB is stable as they get. Running my 4090 no issues. Ever. Free BUMP>......
Sounds like its your RTX card buzzing. I have a 3090FE and at first I thought it was my PSU buzzing because it was 12yrs old and because of the new card. Got a 1300 watt and same thing. It's just the Card electrical whine when it draws a good amount of power.