Why does my FPS drop from 110 to 30 in Phantom Blade Zero high-speed combat?

Every time I entered a high-intensity duel, the frame rate plummeted from 110 to 30 or the game just crashed, which was infuriating. I tried enabling XMP in the BIOS, but the system froze during the memory self-test phase, making me doubt the RAM's quality. I used the GamePP BIOS Load-Line Voltage Adjustment Guide to set voltage to 1.38-1.42V and tRFC to 520. MemTest86 confirmed zero errors over 5 cycles, and HWInfo64 showed temps at 54-60℃ with fans at 1500-1700RPM per Hardware Monitor.