Why does S.T.A.L.K.E.R. 2 have severe frame drops in ruins?

I was so excited to enter this gloomy world, but the frequency scheduling of my Vengeance LPX was a nightmare, jumping between 3200 and 3600MHz. I tried disabling all power-saving options in BIOS, but CPU idle temps soared to 65℃ per HWiNFO64 and the frame drops persisted. I used the GamePP Power Plan Switcher to lock High Performance mode and the Resource Scheduler for Highest priority. FrameView showed frame intervals converged to 11-15ms, and HWiNFO64 confirmed memory temps at 46-52℃.