Your computer will alert you to a CPU Fan Error as it boots up, telling you that there is a problem with your CPU fan error on boot that cools your central processor unit (CPU). This fan is necessary to prevent overheating and damage to your CPU. Dust buildup on the CPU fan, a broken fan blade, a malfunctioning motor, bad wiring, and utilizing your CPU more quickly than it was designed to are the main reasons for this. These elements can all raise the temperature and result in an error.