Fan Curves, Need Help

I’ve been active the last few days with a few posts and I appreciate everyone’s help and input. I’ve been learning a lot delving into things I normally haven’t had to deal with in all my PC builds over the years.

I finally got my thermals under control with my 3900x but had a general question when it comes to setting fan curves. My Radiator fans and case fans constantly would rev up and down based on CPU temps. I found this to be quite annoying so I went in and created a custom profile for both my Krakken X63, The Radiator Fans, and my 6 case fans.

My goal was to keep it as quiet as I could while still maintaining the best performance. It took me awhile to find the sweet spot, but I think I landed on custom profiles that work pretty good. I would like some advice or input if I’m setting it up correctly.

Adjusting my Krakken X63 I found that putting the Pump on Performance provided the best overall noise to performance ratio when paired with a custom profile for my rad fans. I had the hardest time adjusting the rad fan curve; it would fluctuate all over the place. So instead I set the fans to a fixed 1200rpm, if the CPU reaches 70c the rad fans goto 100%. My corsair ML120 case fans I had a way easier time setting the curve. I found the most important spots to fix the revving up and down was adjusting the curve between 40c and 70c. I basically have the fans running slower than default at each point on the curve until about 60c. I basically have my rad fans and case fans waiting a little longer before they start increasing in speeds. So far Idling, Web Browsing, Gaming, and full loads hasn’t changed much in terms of thermals. I would say I’m giving up maybe 4c-5c under certain conditions for better noise levels. This I am fine with since even under 100% load I’m never really going above 70c. In order to maintain these curves I have to have the pump set to performance which is near it’s max, but oddly quieter than I thought it would be.

So my question, should I have not adjusted these curves? Is it not recommended? The default curves had everything revving up to 80% at around 55c which to me seemed like overkill albeit with 5c better thermals, but at the cost of noise. I just want to make sure I’m not doing something stupid.

If your parts stay below the max allowable temperature under full load, then your curve is safe. “Full load” is subjective of course—video encoding is realistic, prime95 is safe, prime95 with AVX enabled will probably overwhelm your cooler, no matter your fan curve.

As long as that condition is satisfied, the rest of the curve isn’t important for safety. The chip might idle slightly hotter or colder, but it doesn’t matter as long as the temp is under the max. Especially since the chip will idle much cooler than when under load, no matter what.

For my own fan curves, I find the minimum stable RPM for each fan. The curve is flat at that level until 20C or so from my max temp, then ramps linearly to 100% somewhere around the max temp. So the fans rev up very aggressively, which can be distracting, but rev down to the absolute minimum when I’m not doing anything, which is great. I know it’s safe because, even at max package power, my CPU will never pass 85C and my GPU will never pass ~80C. At lower powers, the temperature eventually drops to ~40C, even with the fans barely on.

TLDR; your curves are fine, since you say your CPU never goes above 70C. In fact, you could relax your curves a bit and run hotter & quieter safely, although you may lose a bit of performance due to PBO (don’t quote me on that, I have blue chip). Your fan speeds at lower temperatures aren’t really important, as long as they sound good to you.

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I have been struggling with the same issue that the fans ramp up and down. So I thouth that I share my findings / setup.

I’m running Fractal Design AIO and 3700X. I settled for similar setup as you. I have long steady state for 35% PWM for radiator fans. At 55C they ramp up. As this is the state (35-55C) temp fluctuates on normal use. If system is hit wit heavy use fans ramp up Q-fan shot:

Pumps and case fans i keep 80% - 100% (40-60C) as they all are quiet. Highest temps on Tdie/Tctl that I have seen is 65C. This is still new system to me so i don’t know if its hot or not. With this setup fans seem nice and quiet on normal use.

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