Question Case fan won’t spin.

[alliearmstrong]

The main case fan in my computer is not spinning. I have four fans in total, three of which I installed myself which are working fine. The rgb on the default case fan is working fine but it’s not spinning at all. I thought it might have been the bios on the motherboard being out of date so I installed the latest and it’s still not working. Any advice?

Specs
Antec NX400 case
Gigabyte b450 mobo
Ryzen 5 2600x cpu
Gtx 1060 gpu
16gb ram
650w psu

 

[HappyTrails]

Is the all 4 fans connected to 4 pin motherboard headers?

 

[alliearmstrong]

Is the all 4 fans connected to 4 pin motherboard headers?

The three that I bought separately are connected via the power supply. I’m not sure where the case fan that won’t spin is connected.