It is 100% MOBO fan making all the noise. Took it out case to rebuild. Will do new thernal paste too...
As I imagined
System Information Viewer / Smart Fan 5 (AMD AM4 series)
(Note) Support AMD AM4 series motherboards (support may vary by model).
(Note) Please install APP Center first before install this utility.
Not sure on the coil whine from my Corsair RM750X as I've never seen one to compare.
You did the right thing by building your own rig as you have control over everything that goes into it as opposed to something built by someone else who charge you a lot to build it and then it might not be what you really wanted. So good on you for doing that.
If anything is going to fail then it usually is in the early days.
On the control of fans I assume you have downloaded this utility from the site. Just in case
X570 AORUS ULTRA (rev. 1.0) | Motherboard - GIGABYTE Global
The APP center is on the same link
Glad you got it sorted mate,
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