Waterproof Cooling Fan Circuit Design

In the first boot when possible "Waterproof Cooling Fan" too fast or too slow, this time to adjust the 50K variable resistor can change the wind, and then enter the MM inside, quietly waiting for the CPU temperature rises, and as the temperature rises Slowly adjust the adjustable resistance, so that the wind increased, and then take one of the most suitable temperature, say "Waterproof Cooling Fan" by adjusting the variable resistor to control the temperature at 60 degrees, until a few minutes into the game after a steady temperature test machine, and with the CPU running at full capacity, the temperature will rise temperature sensor, control terminal voltage will rise, "Waterproof Cooling Fan" speed will be accelerated, the temperature can be controlled within 65 degrees, but does this circuit fan will appear stepped accelerate, is linearly accelerated, thereby stabilizing the temperature.