Why does my FPS drop from 144 to 80 in dense team fights?

During intense team fights, my frame rate would irregularly drop from 144 to 80, making precise movement nearly impossible. I tried disabling all power-saving options in the BIOS; while drops decreased, temps rose by 8℃ without any real FPS gain, which felt like a poor trade-off. I used the GamePP Resource Scheduler to set the CPU priority to Real-time and forced High Performance mode. RTSS showed frame times stabilized from 7-22ms to 6-11ms, and HWiNFO confirmed CPU temps stayed between 62-75℃.