Why does my FPS drop from 80 to 45 in Banishers: Ghosts of New Eden?

During large-scale spirit battles, the frame rate would suddenly drop from 80 to 45 FPS per RTSS, which severely impacted my operational rhythm. I first tried lowering the voltage in the BIOS to reduce heat; while temperature dropped by 5℃, the performance loss was severe and stutters became more frequent. I used the GamePP Fan Curve Configuration panel to significantly shift the speed curve above 60℃ upward, ensuring the fan reached 1800 RPM before 80℃. CPU temperature stabilized at 75-82℃ per AIDA64 monitoring, and frequency stabilized at 4.4-4.7GHz per CPU-Z.