I'm less than half way through my Ryzen 5900X build, everything bar the GPU is on the motherboard which is in the case, the PSU is fitted and that's it so far. I need to connect the fan leads from the case to the mobo, the two fans from the CPU cooler are connected to the fan headers labelled CPU_FAN and CPU_OPT next to each other on page 1-9 of my ASUS mobo's manual and I'm guessing that I'd connect the fan controller cable from the case to one of the CHA_FANn headers on the mobo? I'm not sure about the power cables though - the 24 pin ATX cable (C) is obvious but on page 1-10 of the manual, there are power connectors The power cables A and B in the manual are 4 pin and 8 pin and the Corsair PSU includes 8 pin cables labelled CPU. So do I plug one of the 8 pin CPU cables into B and then detach/split another 8 pin CPU cable so that it uses 4 pins for connector B? Does power need to be supplied to both connectors A and B?
If your PSU has a second 8 pin CPU connector, they are designed to come apart so you can connect only 4 pins on connector 'A'. Connection 'B' is the standard connection and 'A' is only recommended if you plan on serious overclocking, but your system will function just fine without it at stock or moderate overclocking. Yes, connect the fan controller to one of the chassis fan connections. You don't really need a fan controller though if you have enough chassis fan plugs to cover your needs.
Yep. That's exactly it right there. I would personally always hook up the secondary EPS cable, even if I wasn't overclocking, but it's not strictly necessary.
Thanks, I checked Corsair's website and the 8 pin connector can be separated into two 4-pin ones, so I guess I will use it for connection A seeing as it's provided. For the fans, the case has a PWM hub with the existing fans already connected and I see there's an "input" header on the hub so I just need to connect the cable from that to the header on the mobo, so that the PWM hub can control the fan speeds. The Noctua heatsink comes with a Y-connector for the fans so in the interests of tidiness, I might make use of it to connect both fans to CPU_FAN on the edge of the mobo and then connect the case's PWM hub to CPU_OPT
The Asus TUF B550 motherboard I've had ties fan control CPU_OPT to CPU_FAN, it is not possible to have a separate fan profile for those 2 ports. Something to keep in mind if you want to control the chassis fan separately. I recommend plugging it into FAN_CHA or something similar, giving you option to control fan speed separately from CPU temperature. Eg. use the motherboard temperature sensor.
Cheers, yes the manual does say that they're "shared control" - I wouldn't want to the case fans to be tied to the CPU fans (doh!). You're absolutely right and CHA_FAN2 header is usefully located at the bottom of the board in the case, so I'll use that to keep the cabling tidy.
