Rem0o
Cannot detect speed sensors for fans with V249 even though they were working fine before
Describe the bug The update to V249 somehow bugged my entire fancontrol setup. Prior to the update, all my fans were detected by the controller just fine and were set up on a normal curve. However, with the update, the controller can only detect two of my case fans and my GPU. I have an ASUS Prime B650-PLUS WIFI motherboard.
Is there a log.txt file next to FanControl.exe with recent date entries? [Link it here]
Relevant hardware specs and setup ASUS Prime B650-PLUS WIFI motherboard AMD Ryzen 7 9800X3D Corsair RM850x Case fans connected to a driver, all connected to one motherboard slot.
Same here
AsRock Nova WiFi x870e AMD Ryzen 7 9800X3D Not a single sensor gets detected. I suspect it may have something to do with the upgrade to .NET 10
[V249] 11/20/2025 9:25:16 AM: Startup - System.Exception: Sensor validation failed: The following sensors are missing: /lpc/nct6799d/temperature/3 /lpc/nct6799d/control/0 /lpc/nct6799d/control/1 /lpc/nct6799d/control/2 /lpc/nct6799d/control/3 /lpc/nct6799d/control/4 /lpc/nct6799d/control/5 /lpc/nct6799d/control/6 /lpc/nct6796dr/control/0 /lpc/nct6796dr/control/1 /lpc/nct6796dr/control/2 /lpc/nct6796dr/control/3 /lpc/nct6796dr/control/4 /lpc/nct6796dr/control/5 /lpc/nct6796dr/control/6 /lpc/nct6799d/fan/0 /lpc/nct6799d/fan/1 /lpc/nct6799d/fan/2 /lpc/nct6799d/fan/3 /lpc/nct6799d/fan/4 /lpc/nct6799d/fan/5 /lpc/nct6799d/fan/6 /lpc/nct6796dr/fan/0 /lpc/nct6796dr/fan/1 /lpc/nct6796dr/fan/2 /lpc/nct6796dr/fan/3 /lpc/nct6796dr/fan/4 /lpc/nct6796dr/fan/5 /lpc/nct6796dr/fan/6
https://github.com/Rem0o/FanControl.Releases/issues/3686#issuecomment-3536245023
I have similar issues. Everything was OK on older version, then I decided to update since it's been a while. Now all my sensors/fans except for my NVIDIA 2080 Super are showing up. The rest; pump, case fans, and AIO fans are all gone. I tried downgrading to different versions but without any success so far.
| Type | Device Name |
|---|---|
| AIO | Liquid Freezer III Pro 360 |
| PSU | Corsair RM750i, 750W |
| Standalone fans | Corsair ML120 PRO RGB, 120mm 3-pk |
| GPU | ASUS GeForce RTX 2080 SUPER ROG Strix |
| MOBO | Gigabyte X570 AORUS ULTRA |
Edit: Fixed it. It was not the update itself for me, it was PawnIO not being able to start after installation due to seemingly FaceIT Anti Cheat (it wasn't running but it was installed). I removed it. #3505 (comment)
/lpc/nct6799d and /lpc/nct6796dr have changed identifiers without me noticing. They should still be there but with a different name, unconfigured.
How should I move from here? I don't have Faceit AC installed, and reinstalling the PawnIO driver didn't resolve the issue. I'm also assuming that downgrading the version wouldn't have any effect either (according to previous comments).
@toolboxV Try starting LHM and see if your sensors are being displayed. https://github.com/LibreHardwareMonitor/LibreHardwareMonitor/actions/runs/19545993316
Downgrading back to v245 worked for me. I'm just gonna stay here until whatever this is gets figured out. Any time I try to upgrade past it, my CPU sensors disappear.
Check if LHM can see your sensors. If yes, then the sensors are in FanControl too, but you likely need to "add them back" as the linked comment states.