Why does Lost Ark FPS drop in crowded city areas with many players?

Gathering in the bustling city center, the frame rate plummets from 120 to 45 as more players appear, making the experience choppy. I first tried enabling Power Saving mode in Windows to reduce heat, but the FPS halved to 30, a counterproductive move that made me anxious. I accessed the GamePP Fan Curve Configuration Panel, raising the 65℃ speed from 50% to 80% and optimizing the sampling cycle. Frame times converged to 8-12ms via Frame Time Analyzer, CPU temperature stabilized at 68-75℃ per AIDA64, and fan speeds hit 1200-1500 RPM per GamePP Hardware Sensor.