Why does my Gainward RTX 2060 Storm keep jumping clock speeds and dropping frames in Dying Light 2?

Sprinting through the city ruins was a mess; my frame rate would suddenly tank from 55 FPS down to 32 FPS, and that choppy feeling was driving me insane. I fired up HWiNFO and saw the core clock on my Gainward RTX 2060 Storm bouncing wildly between 1400MHz and 1850MHz, which sent my frame times swinging from 16ms to 42ms. My first instinct was to slap 'Prefer Maximum Performance' in the NVIDIA Control Panel, but that was a mistake—temps spiked to 84℃ and triggered a thermal throttle, making it even worse. I eventually switched to MSI Afterburner and manually locked the core clock at 1750MHz while nudging the voltage to 1.02V. After running an AIDA64 stress test, the frame times finally settled into a tight 14-15ms window. I did notice the fans got about 8dB louder immediately after locking the clock, but I fixed that by drawing a custom fan curve. Now it stays between 68-74℃ and feels rock steady. I saved the whole profile to my motherboard's onboard storage so it loads every boot.