Question Case fan causes pc to shut down.

Jul 25, 2019
I bought a new case since my old one was breaking and It coes with and RGB strip built in at the front and an RGB fan in the back. The fan in the back has two cables connected to it. One small 3 pin connector which is connected to the front panel RGB, and a molex connector which I have plugged into my non modular power supply. The fan did not turn on so I plugged in the 4 pin cable which is part of the same PSU molex cable bundle, into the mobo system fan, however this shuts the pc down and does not allow it to start up. I have change the system fan slot to be PWM in the bios but nothing seems to work.

Any help or suggestions would be greatly appreciated.