Solution to Excessive Fan Noise in Home-Used HP DL360p G8

I bought a dl360p g8 a few days ago. The fan noise during the power-on self-test was very touching. After booting up, the fan speed remained at around 49%, and the noise was still very loud. It is impossible to keep it at home.

After entering ILO, I found that the values of each temperature sensor were not very high.

After consulting some information, I decided to manually reduce the fan speed to reduce noise.

This is the fan interface definition diagram of dl360p g8, where GND1 and GND2 will be short-circuited to test whether the fan is installed normally on the motherboard; Tach1 and Tach2 are used to test the fan speed;The motherboard adjusts the fan speed via the pwm pin.

As long as we connect the PWM lines of each fan in series and send PWM signals externally, we can take over the control of the motherboard and manually adjust the fan speed.

1. Line transformation

Short-circuit the four pins GND1, GND2, Tach1, and Tach2 together to deceive the motherboard.

Then connect all the fans' pwm lines in series

2. Manual speed control using Arduino

Sending a pwm signal to a fan using arduino

The procedure is as follows:

int control;

void setup() {
    pinMode(3, OUTPUT);
    pinMode(4, OUTPUT);
    pinMode(5, OUTPUT);
    pinMode(6, OUTPUT);

    digitalWrite(4, HIGH);
    digitalWrite(5, LOW);
    digitalWrite(6, HIGH);

    // 先将风扇转速调零
    analogWrite(0, 255);
}

void loop() {
    control = analogRead(A0) / 4;
    // 发送pwm信号
    analogWrite(3, control);
}

An external knob is connected to the Arduino for manual speed adjustment.

Finally, you need to add a 5V small fan to the raid card for separate heat dissipation(Or the temperature is too high 233)

Effect video: