Why does my Cooler Master B360 Core ARGB pump speed jump around and cause overheating in Far Cry 6?

While raiding outposts in Yara, my frame rate would randomly tank from 90 FPS down to 35 FPS, making stealth plays a total nightmare. Checking HWiNFO, I saw the Cooler Master B360 Core ARGB pump speed swinging wildly between 2100 and 2800 RPM, which sent core temps spiking from 62℃ to 88℃ in seconds. I first tried the BIOS smart control mode, but the pump stayed too slow during low loads, causing heat to soak the block—a logic flaw that honestly left me baffled. I eventually forced the pump header to Full Speed in BIOS and used fan control software to trigger the radiator fans at 55℃. The temps finally stayed locked in a tight 65-72℃ range, and frame times tightened from 18-42ms to a crisp 11-14ms. I did hit a snag where the pump made a high-pitched humming noise at full blast, but swapping the radiator mounting gaskets fixed it. CPU power draw stayed between 115-130 Watts, and the temp curve is finally flat. Everything is saved and running smooth now.