I'm using c6h wifi motherboard with 3700x CPU and currently experiencing a lot of problems with fan control / sensors on recent bios versions. I did expect some problems when i was building this system (bleeding edge bios, etc), but i never thought there will be so much issues with such a basic functionality as temperature control.
I have 1 CPU fan and 3 PWM case fans (Noctua A14/A12). #1 and #2 case fans should change RPM depending on CPU temperature, and #3 depends on PCH temperature. Basically it works fine for some time (usually 2-10 hours), but then the expected behavior breaks in many different ways:
1. This is the most common issue i'm experiencing right now. Usually fans should spin around 800-900 RPM when the system is in idle state. When this problem happens, RPM decreases to 400-500 and the more i load my CPU the less RPM i get until fans completely stop
. And it happens to all CPU-related fans. This is so ridiculous i even made the video — https://streamable.com/i3379
where you can see the idle behavior (~400 rpm) and what happens when i load my CPU using 'stress' utility. I've tried different fan profiles (silent, standard, etc), different low speed, delays and nothing changed. I've checked and can confirm that fans are really stopping, so it's not just monitor tool issue. The fix is to reboot the system.
2. Motherboard temperature sensors just stop working and hang up on the last value it was, even though RPM sensors still work. Once more, it's not the monitoring tool related problem because fans aren't changing the speed if i load my CPU. For instance, if CPU temperature hangs up on ~50C temperature, fans will still have ~800 RPM even if i stress my CPU (usually in this case RPM should increase up to 1500). The fix is to reboot the system.
3. Fan is just completely ignoring the component's temperature. I had this issue on my fan #3, which wasn't changing idle RPM even though my PCH temperature was already around 80. The fix is to reboot the system.
4. Fan gets stuck at 100% RPM. This usually happens on my fan #3 when i cold boot my system. Rebooting the system didn't help me though, i had to clear CMOS (or make some changings in the bios) to fix this.
So basically my system is barely usable right now, i have to constantly monitor the sensors and regularly reboot my system when something breaks again. Otherwise this behavior can possible damage my CPU/motherboard due to overheat in high-load scenarios. As far as i can see, other people are experiencing pretty much similar fan-related problems i do, so it's not just defect motherboard i have.
I've been using ASUS motherboards for 17 years starting from P4PE and you can imagine how disappointed i am right now. In my opinion this kind of issues are critical and should be investigate ASAP. I hope my report can be useful, and this situation won't end with changing motherboard to another vendor.