Problem with the CPU cooler not functioning.
Problem with the CPU cooler not functioning.
Hi there, I'm building my first PC on my own and everything seems to be functioning well. However, I'm having trouble getting the CPU fan header to power the fans. My system uses a ROG STRIX B450-F with a Ryzen 3600 processor. The motherboard includes multiple fan headers like CPU_Fan, CPU_Opt, CHA_Fan1-3 and AIO_Pump. There are six fans in total. I've connected the three case-mounted fans (Corsair LL120) to the chassis fan headers and am using them for my AIO radiator (Coolermaster Ml360r). The other three fans that came with the radiator are being used as chassis fans. The radiator has a fan splitter, so initially I connected all three to the CPU_Fan header, but they didn't spin and the boot process failed because the motherboard flagged a CPU fan error. I've tried swapping fans and changing headers, but it's still inconsistent. Sometimes the CM fans work fine when plugged separately or with the splitter on CHA_FAN1, while others don't. When I power the PC on or off, the connected fans sometimes jerk slightly. This suggests there might be an issue with the CM fans and their headers, but I'm not sure what's causing it. Thanks, Liam
It might stem from the motherboard headers lacking sufficient power to run all your fans. I’d be cautious about trying to run six fans solely through the motherboard connectors—splitters can help, but you risk overloading one header and damaging it. A good option is a quality 5.25" fan controller that fits in an extra optical bay slot; these usually have stable power via SATA or MOLEX connections. If your case doesn’t have an optical port, you’re stuck with multi-splitter connectors, often found on eBay for RGB fans with remote controls. Investigate the available types and choose a solution that matches your setup. I own a Coolermaster Cosmos II case supporting around nine fans, but all of them draw power directly from the case itself; none of the motherboard headers are utilized except the CPU fan’s AIO pump. Proceed carefully to avoid overloading any header.