Fan Problems with H115i Pro

Hello, I just recently upgraded my old H115i to the Pro model. I did so because my new case is shorter than before and didn't allow the thicker tubes on the old model to fit inside and bend to the CPU socket. Along with installing the new AIO, I downloaded the iCUE software to go along with it. I created a custom profile in iCUE with a fan curve identical to the one I was using with the older H115i with Corsair Link, and I mapped the graph to correspond with the CPU package temperature. Here's where the problems arise.

 

Whenever my processor comes under an intensive load, the fan speed shoots up way above the limitations I set on my fan curve. For the temperature my processor was at, the fan speed should've been around 1000rpm and instead it was around 1600rpm. The first time that happened I double checked the curve in the software to make sure it saved, which it did. The second time, I abandoned my custom curve to try a default one, specifically the quiet preset, and the problem still persists. After a few times of trying different profiles in iCUE and getting the same results I finally set the fans to a fixed RPM, which did work. Funny enough, fixed speed percentage doesn't work. I tried setting my fans to 10% and the RPM again shot up to 1800 rpm. So after no luck with the profiles in iCUE, I thought maybe Corsair Link would fix the fan curve problems. Unfortunately, the exact same issues happened with the exact same profiles regardless of which software was being used.

 

So I don't know where to go from here, the reason I posted this thread in the cooling section and not with iCUE threads is because the only component I haven't troubleshooted that must be the problem here is the AIO itself. I don't know if I have a case to RMA the unit and get a new one, or if there is a magic switch somewhere in the software that I'm not seeing that will clear up my problems instantly.

 

Also, the fans I'm using with the H115i are a pair of ML 140 pros. They are the same fans I used with the older H115i so I can't imagine they're the cause of the problem, but in case they are that's them. I appreciate any help you guys can give me, thanks.

First, there are still a few quirks with fan control in iCUE. One of the more obvious ones is switching from fixed speed back to your normal curve will cause a momentary max fan spike. The fixed % should work, although the fixed rpm is accurate and probably more useful. I suspect the problem is 10% is below the ML140 Pro minimum. Mine will do 400 rpm, but not 200. That’s a big ask from a 2000 rpm fan.

 

One thing you can do to get away from this issue is use the coolant temperature (H115i Pro Temp). Using CPU temp offers no cooling advantage, ramping fans, and is probably just plain crazy on Kaby/Coffee Lake. The cpu temp could change 5-6 times for every polling interval. All your limits on the 8600 will be materials and voltage. You probably have a relatively small 4-5C coolant temp rise and that means even at maximum fan speed you can only reduce the cpu temp by 4-5C. No reason to run 2000 rpm for that. My 8700 is at 1.30v and my coolant delta still peaks at +5C with 600-800 rpm on the HD140s.

 

I don’t recommend any of the default fan presets unless you are in a cold and steady room. These things are affected by room temp more than anything. You can make on suitable for your environment in 30 seconds and that is always the better option.

Ok, I’ll switch the graph reference and see if that works. Still doesn’t explain why on presets like “Zero RPM” the fan speed maxes out instantly. But maybe if what you said works I can just avoid that preset and not have any problems. Thank you

"zero rpm mode" only works below 35C coolant temp. You can reach that value in Summer without any extra load and when you do, the fans and pump go to maximum. Zero RPM mode also only works with the stock ML-Quiet fans.

 

You'll have to figure your normal coolant temp range. Wherever it stays steady while idling on desktop can be the quiet baseline. Set a gradual increase in fan speed about +3C down from the normal. You don't need it change speeds for 1-2C of change and that gets more complicated with room temp changes. Figure out the highest coolant temp you are likely to see and set that at a moderate, but tolerable fan speed. Save the high RPM blast for +5C past that. If something is out of line, you will hear it before you see it. If you live in a temperate climate, you will probably need separate curves for Summer and Winter. My Summer baseline is above my Winter peak, with a definite 10C difference in room temp between the two seasons. That is double my normal coolant rise and a much larger factor.