Hi dan4o84,
Normally, when using further, system resources, or the use of the graphics card (as in games) it is normal that the temperature increases.
So if the temperature increases, the fans will run faster.
And then there will be more noise from the fans.
But you seem to say that there is electrical noise from the power supply.
In order to verify beyond any doubt, the origine of this noise, it would be to disconnect all the fans of the system.
You will hear more noise and where it comes from.
I imagine that you check if it is a noise caused by vibration of a part of the tower or other equipment.
It will also be a test to see the difference in temperature.
Of course the ventilation of the graphics card is the only one to operate.
After having properly identify the source of the noise, you can reconnect the fans.
Maybe not all, depending on the test temperature. You will have less noise too.
Gloup_Gloup