retrolefty:
Could be a conflict on internal timers used depending on what pins you are using for the servos and pwm fans. Again from the reference:
Thank you retrolefty!
But in my setup, Arduino Mega is used and pin 11 and 12 are avoided.
Here's the distribution with trouble (while only 5 fans and 10 servos are connected):
10 pins for analogWrite()PWM: 2-10, 13
20 pins for servos: 22-31, 34-43
And the stable distribution is (Also, 5 fans and 10 servos are connected):
5 pins for analogWrite()PWM: 7-10, 13
10 pins for servos: 22-26, 34-38
The previous one, theoretically, should supported by Arduino Mega, according to the reference...but the servos were still shaking.