Select "Auto" for automatic fan speed adjustment or "PWM" for precise control via pulse width modulation.
Select "Auto" for automatic fan speed adjustment or "PWM" for precise control via pulse width modulation.
Hello everyone, I wanted to clarify a few points. English isn't my first language, so I hope you're following along. I visited the BIOS to look for CPU fan settings, checked all sections except the final one about "PC Health Status." There I found "CPU Smart FAN Mode" and it was set to "Auto." I explored further and noticed options like "Voltage" and "PWM." After searching online, many suggested that "PWM" performs better than "Auto." I decided to switch from "Auto" to "PWM" based on their advice. My main question is: what's the difference between these settings? Is "PWM" actually more effective? Could it be the better choice? Also, I have a 4-pin CPU fan and a matching 4-pin motherboard header—everything seems compatible. Thank you for your help!
Auto selects between two choices: Voltage in DC mode, or adjusting the fan speed via PWM on the fourth pin of the header. PWM offers finer, smoother control compared to steps, reducing noticeable noise. Both Auto and PWM work well together for a four-pin fan. Setting PWM to active is fine.
Auto decides which method it should apply—PWM or Voltage—based on your fan's capabilities. Choosing PWM means you're using a model that supports pulse width modulation, while Voltage refers to adjusting the voltage to alter the fan's speed. PWM works by rapidly switching the fan on and off, changing its speed, whereas Voltage changes the electrical input to affect RPM. For more details, see the article on PWM and its function.
Someone might not grasp how it functions when they hear "auto" is preferred over PWM. The board usually handles things better than the user does. I rely on my software and perform a fan learning without any problems. The exception comes on my other setup, which uses all 3-pin fans, so I switch to DC and do another fan learning.
Thanks for letting me know. I should have understood that Auto picks one of the two options. Appreciate the clarification!
It seems you're confused about how the system decides between Auto and PWM settings. Both options are essentially similar, with the main difference being the voltage selection.
It should rely on PWM when the fans are compatible (as yours are). Otherwise, it would revert to using voltage.