There’s no shortage of cooling capacity in my system, so the real question is how quiet I want it to be, and what thermal limits it needs to keep within.

Based on some reeeally vagues ideas from an Optimum Tech video, a GPU temp of ~60°C is okay for a gaming load, with CPU around 55°C.

Under a pure CPU workload he’s showing temps in mid 70s as okay, but that’s a 12700K that has a much larger power envelope – about 140W for my 5800X vs 190W for the Intel chip.

That video assumes rad fans around 1000rpm, and pump around 2000 rpm. Because I generally have headphones on, I’m happy to run rads at 1400rpm under load (75% PWM), and the pump is so damn quiet that it doesn’t really matter what setting it’s on.

PWM percentageFan RPMPump RPMNotes
75%14503925Max speed, only when loop temp hits 38°C
66%12503400Pump is quieter at 66% than 60%
60%11803080Pump resonates, noise is just noticeable
40%7801950Idle speed, stays here while loop temp below 28°C
I’m not exactly sure how Smart Auto is meant to differ from a Linear curve, but I guess it works well enough.

I’m pretty sure I could safely pull the top of the curve right down, I don’t think there’s much drop in coolant temp by running the fans beyond 1250rpm. I need to do some heavy gaming and see how bad the temps get, just find what temperature the coolant stabilises at for a given CPU and GPU temperature.