Asus H87M-Pro board attempts to manage voltage for a PWM fan
Asus H87M-Pro board attempts to manage voltage for a PWM fan
You can choose between PWM and DC control for the chassis fans via the Q Fan section in the BIOS menu. After enabling Q Fan control, locate the fan speed adjustment area in the top right corner of the screen, where you can set both fan speeds and view speed graphs.
I don't locate that part. It seems the Q-Fan control is active, but no additional fan configurations are available beyond what's already discussed. Updated May 8, 2024 by Average Nerd
I set up an Arduino as a fan controller while you worked on it. I plan to install the AI suite later and will let you know the results.
You should be able to go to RPM mode and set a certain speed. Mind sharing a wiring diagram for the adapters you made? I'm wondering if there's something funky there, like 2 fans to 1 header with both reporting their PWM speed.
I think it should be clear now. The diagram was created quickly. The fan is sending its speed data to the board correctly, though PWM isn't functioning properly—only the Arduino is working. The same adapter performs well with both the CPU fan and the main board.
This may be the difference (from the manual): Your CPU adapter must be triggering the special latch, hence it works in PWM mode. All other headers are standard, and auto-detection must be based on the number of attached wires (4=PWM, less than 4 = DC). Sucks to not have a manual option, only auto.
I observed something unusual: connecting a standard 4-wire fan to the chassis fan header doesn't allow Fan Control to adjust its speed. Removing one of the server fan hubs also doesn't help, as the remaining hub still operates at full capacity and isn't controllable.