Hi,
Background: I have installed a USB header splitter (Bluetooth and Corsair iCUE Node Core).
Problem: My CPU fan is not spinning on the port (CPU_FAN; CPU_OPT) that I have for it. It does spin at startup but then stops. The mainboard does not recognize the fan when it is plugged in. I have now unplugged a case fan and plugged in the CPU fan, now it spins. But that can't really be the solution.
Mainboard: AORUS B550 Elite (V1; rev. 1)
CPU: AMD Ryzen 9 3900X
I already had to replace the motherboard last year because the CPU fan didn't started anymore. Have any of you had the same motherboard and the same problems? I can exchange the motherboard but for an AORUS B550 Elite V2. Does the V2 motherboard still have this problem?
ICUE might be messing with the bios fan control ?
I think not, i'm using SignalRGB
Are you using the CPU Cooler that came bundled with the Ryzen 3900x - AMD Wraith Prisim?
If you connect the Prisim to one of your Computer case power ports (3 Pin port) does it turn on and stay on?
Try turning off AMD Cool&Quiet in BIOS>Tweaker>Advanced CPU Settings
Then go to Settings>Smart Fan 5 and you can try Manual Fan Speed Control, change Temperature Input, and make sure Fan Stop feature is Disabled.
Have you checked the bios settings and/or tried different headers?
I had the same problem. I installed new mobo, Asrock Steel Legend B550, and I have a Coolermaster AIO cpu cooler with 2 Thermaltake 120 RGB Ring 2 fans on radiator and one in back over io shield. I have 3 of the same fans in front of case. When I first booted the fans spun up, the rgb came on, then they all stopped. I was a little worried about my new cpu Ryzen 5 3500x so shut it down. Restarted and went to uefi screen and all the fans in it were set to silent mode. Changed the ones I had connected to standard mode and everything was as it should be. I hope this helps.