Why does Farming Simulator 25 cause FPS drops on my CPU?

I was devastated when managing thousands of acres caused my frame rate to plummet from 90 to 45 FPS, totally killing the vibe. I first tried setting the fan mode to full speed in BIOS, but it sounded like a drill in my ear while temps stayed above 85℃ per AIDA64. I finally used the GamePP Fan Curve Configuration Panel to set 70℃ as the ramp-up threshold and optimized the pump voltage. Now, my CPU frequency is a rock-solid 4.8GHz per RTSS, and temps sit at 72-78℃ per AIDA64 with pump speeds at 2200-2400 RPM.