Pin Number |
Pin Name |
Description |
1 | Sense |
yellow or white // from fan |
2 | 12 V | red // fix voltage |
3 | GND | black |
4 | Speed | blue or green // from mainboard |
5 | NC | unused |
Measurements with CPU heat of 40°C:
Sense puls: ca. 27 Hz ( duty cycle 50:50), 3.3 V
Speed puls: ca. 2 usec and 43 usec pause, 3.3 V; probably a pwm puls
The fans that connect to the header are: Model AFC1212DE , DELL PIN: MJ989.