CPU activity and CPU cooler

My cpu cooler seems to rev up periodically for some reason. Always when I’m at an airport in drone mode low flying over lets say Chicago Midway. When I stop droning over the terrain the cooler revs down. I can see the CPU utilization jump in task manager then the cooler revs up until I stop the flyover and within 10 seconds it ramps down. This periodically happens when I just have the sim paused or just sitting and I open a chrome window to a website. Also it seems as the sound is coming from the cooler’s “Inner” fan only as the outer fan doesn’t seem to change rpm’s when it revs up (I could be wrong here). When the cooler revs the GPU fans stop spinning until the cooler ramps down then the GPU fans start to spin again.
This isn’t normal is it?

PC Specs:
7800x3d
4080 super
Dark Rock Pro 4
Gigabyte B650 Gaming X AX
Seasonic Focus+ 850

This is normal. The cpu cooler fan ramps up in response to the load on your cpu (which is higher in dense areas and when moving quickly as there are a lot of calculations to do unlike when moving slower/stopped or in remote areas). The GPU fan operates independently of the cpu fan and is simply responding to the temp/load of the GPU and it will scale up and down as the GPU load moves. Your system is fine.

Another thing to consider is what type of CPU fan it is, 3-pin DC (Direct Current) or 4-pin PWM (Pulse Width Modulation.) PWM fans can have a lower minimum speed. I have two fans on my CPU air cooler. They both connect to them motherboard header.

Both types have fan curves associated with them. Assuming your CPU fans are connected to the ‘CPU Fan’ header on the motherboard, the curves are editable in the BIOS.

Not mine, but this graph shows a curve that keeps the fan at low RPM until the core temp reaches 60°C, then rapidly ramps up above that temp.

Ok thanks guys. Good to know. BTW my Dark Rock Pro I believe is 3-pin. Also is 60 degrees a good temp to have the fans set to ramp up?

I would strongly recommend the excellent (and free) Fan Control app. With it, you have control over every fan inside the case, including those on the GPU. You can link them all together via various sensors to respond to demands exactly as you describe by ramping everything up together. This is quieter and avoids individual hotspots inside.
There are a lot of control options so it can take a little tweaking and setting up correctly, but there is a good introduction and explanation video from J2C here:

Everyone NEEDS this FREE piece of software… You will thank me! - YouTube

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Thanks for the advice and youtube link. I will try to take a look at it this weekend when I have some time and let you know how it goes.