Fan Dc Mode Or Pwm Mode

Whereas with dc mode fans are speed controlled by varying the dc voltage supplying them.

Fan dc mode or pwm mode. There are often additional fan ports exclusively for the 3 pin variety. Dc motors can work even with voltages lower than the nominal one. I tried setting all fans to full speed because i don t mind the noise but it looked like while doing that it changed some over to the opposite mode. All fans have a dc voltage supply or they wouldn t run.

Every fan uses a dc motor. Pwm fans have a 12v dc supply and vary their speed based on the pwm control signal on the 4th wire. So my personal opinion. Maybe vise versa i guess i ll have to double check.

You are best to define a case airflow strategy that uses mostly pwm fans. A hybrid pwm dc header is the best of both worlds since it can be configured for each type of fan there are even autosensing hybrid headers. The pwm signal is either generated from a control voltage derived from subtracting the output voltage from the reference voltage combined with a sawtooth waveform running at the clock frequency for the voltage mode regulator or by adding a second loop feeding back the inductor current for the current mode type. My fans are on full blast as long as my pc is on.

Even so some boards like my asus allow either dc voltage control of 3 pin fans or pwm control of pwm fans. I can toggle between dc and pwm mode in the bios. When a lower voltage is applied the motor runs more slowly. I know that the fans i have are dc because they only have 3 pins but my motherboard can support 4 pin fans.

Supposedly i can also change the profile and speed for my case fans but literally none of the options make a difference. It looks like cpu fan was already on pwm and chassis fans were already on dc. 2 this would have to be true dc mode means dc voltage control.