If you overclocked your system and the CPU should not pass 45°C otherwise it crashes. Well you set the limit of the sensor you placed near the CPU’s heatsink to 45°C. As soon as you hit 45°C the Ultracool starts beeping and gives full power to all fans, this causes the temperature to drop to 44°C, the fans slow down, the temperature goes up, beep beep, fans speed up, temperature goes down, fans slow down, temperature goes up…you get the picture.
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