0

Hello all I recently purchased a R9 380 OC STRIX asus graphics card and I noticed quickly after installing the card that when the system runs POST the graphics cards fans do not turn on which concerns / pretty much scares me greatly. I quickly found that the graphics card comes with 0db technology stopping the fans from running under a certain temperature threshold and I personally wish to test the fans because I don't see them working at POST and I generally just want maximum cooling. After doing some googling I found out that a Windows program (ASUS graphic tweak II) can control the graphics card but I primarily use linux and do not have a working Windows installation.

This leads me to three questions. Revolving around this issue: 1. If anyone knows this line or style of card activates its fans during POST.

  1. Is there a way to access and control the fans in linux.

  2. If the answer to question 2 is no could anyone tell me if the changes made by the windows program change the cards behavior when the program is not running and or I'm not using a Windows install. I have read conflicting information on web on whether this acts like a service or actually changes some value in the firmware

Zeno of Elea
  • 18

1 Answers1

2

Googling for amdgpu fan finds this project. Looking at the source, the kernel module exposes fan control on the /sys FS via the hwmon interface.

So you can either write directly to the pwm* files in

/sys/class/drm/card*/device/hwmon/hwmon*/

(with the correct path for your actual hardware, of course), like the script does, use the lmsensors package your distribution is sure to have, or use a script like the above or other program that does the control for you. The hwmon link above explains the files and the values you can write to them.

Given the kind of interface that is exposed, it's very likely that under Windows a driver controls the fans, so they are not "activated" during POST, and anything Windows does doesn't cause permanent changes. And "0db" is just a fancy name for the control in the driver. That's a guess, without having access to the source code of the Windows driver it's hard to say anything definite.

dirkt
  • 17,461