nVidia chipsets do tend to get hotter, it's normal for them, we can't do much about that.
For the CPU, your motherboard fan header is 4 PIN right? Then you should have in BIOS a setting for the installed fan type, where you can set it to PWM for 4 pins and to DC for 3 pin. See that it is on DC.
Fan controllers should be on Disabled for max speed, or Turbo for quiet when cold, but fast when hot.
If you ran OCCT for a long time now, then temperatures aren't so bad at full load, so to me it seems that the fan is running at a very low speed when in idle, to be silent. Right now, it seems OK to me, you might just have the Noctua that only gets to 600-800rpm? There should be one with 800-1200 rpm. So higher temps then you would get with a 1500-2000 rpm fan should be expected. The actual rpm should be in BIOS and should be accurate.