Question System shut down but fans keep spinning

[NightHawkRMX]

Problem: When the system is plugged in, immediately the case fans, GPU fans, and PSU fan begin to spin.

I can power the system on and the LEDs light up on the fans. The system boots and works properly.

If I shut down from within windows the PC seems to shut down but these fans stay spinning constantly. I have tried holding the power button and the system shuts down with the same fans still on, although usually the RGB stays lit too when I shut down this way.

Specs:
Cyberpower C series
Ryzen 5 3600
Gigabyte B450M DS3H Wifi
Gigabyte 1650 super
Apevia Prestige 600w Gold PSU

Note: On these cyberpower cases, there is an led strip, led cyberpower logo, and 3 argb fans that plug into a built in controller. Then from the controller there is a single argb connector that plugs into the board. The built in controller takes a sata power input. The fans each also take molex for power.

What I've tried:
Updated bios to latest
If I unplug the 24 pin with the fans spinning but PC off the fans all stop spinning, including the molex fans connected directly to the PSU.

Does anyone have any experiences with a similar issue or have any idea of what could be wrong with it?

 

[helpstar]

PSU
motherboard argb
or fan controller

 

[NightHawkRMX]

Threw in a known good PSU, same problem.

I discovered the issue, you are right it was a combination of the argb header and the fan controller.

I discovered if I unplugged either the sata power or the argb header to the controller the fans all stopped spinning. What I believe is happening is that the 5v standby the argb header uses to have LEDs on with the PC off is back feeding into the PSU from the sata connector on the controller, which is causing everything to get power and spin.

Seems like a very poorly designed controller built into this case, I've never had this happen before.

So if anyone else runs into the same issue: you can have either the argb or the sata plugged in at once, but not both. The controller works fine with the argb input from the board if I unplug the sata connector. If I use the sata connector and unplug the argb I can use the case buttons to control the rgb.