I recently purchased a PC from Facebook Marketplace, and while it seems to be functioning well, the fans are running at full speed continuously. The previous owner mentioned that he plugged them directly into the power supply unit (PSU), which I suspect might be causing this. Does anyone know how I can resolve this issue? Here are my specs for reference:
- CPU: Intel i7-10700F
- Motherboard: MSI B460m Pro-VDH WiFi
- GPU: RTX 2080
- RAM: 16GB DDR4
- Storage: 500GB SSD + 1TB HDD
- PSU: 650W 80+ Bronze
- Cooler: Corsair H150i
1 Answer
It sounds like you need to connect the fans to the PWM header on your motherboard. When they're plugged directly into the PSU, they typically run at full speed all the time.

Where can I find the PWM header? I see a sys_fan, cpu_fan, and pump_fan on my motherboard, but no PWM.