Why does my CPU keep throttling and dropping frames during heavy combat in Destiny 2 with an RT620 ARGB?

During massive ability dumps, I noticed these micro-stutters that completely broke the immersion. The PCCOOLER RT620 ARGB has the bulk, but the default silent profile is a nightmare; it doesn't even start ramping up until the CPU hits 74-80℃, by which time the cores have already throttled. I tried slamming the system into 'High Performance' mode, but that just made my room sound like a jet engine without actually dropping the temps—total waste of time. I eventually dove into the BIOS and pushed the fan trigger point down to 58℃ using a stepped acceleration logic to get airflow moving before the heat spike hits. Checking HWiNFO, the clocks finally leveled out between 4.3-4.6 GHz, and frame times tightened up to 8-12ms. I actually messed up the first few curves by making the steps too narrow, which caused the fans to rev up and down constantly, but adding a 3-second hysteresis fixed that annoyance. Now the CPU sits comfortably at 66-72℃ with fans humming around 1300 RPM. The load curve is finally smooth, and the input lag is gone.