Why does Genshin Impact drop frames on KingBank DDR5 6000?

While exploring Teyvat, the frame rate would drop to 45 FPS without warning, making combat stressful. I tried running the Windows Memory Diagnostic tool, but it showed everything was normal while the lag persisted, proving software tests couldn't detect these fluctuations. I used the GamePP BIOS Load Line Voltage Guide to lock memory voltage at 1.35V and set VCCSA to 1.20V. AIDA64 showed a flat stability line, GamePP confirmed 6000MHz stable, and HWiNFO verified memory temps at 51-56℃.