H100iv2 Problems and iCue Crash

So recently I've built a new gaming PC, first time using an AIO cooler. I replaced all fans in my case with ML 120 fans (5 RGB and 2 Non-RGB). I've set up the h100iv2 as a push/pull intake (2 pull fans connected to the PWM strip coming out of the pump and 2 push fans connected to a Silverstone PWM fan hub that has all other fans connected to CHA_FAN1). **This issue happened with just a push setup with stock fans and all case fans connected to MOBO fan slots**

H100iv2 is connected to the CPU_Fan which is set to full speed in the bios and q-fan control is disabled.

I mainly play Fortnite (Custom for locked 165fps) or Destiny 2 (high settings) in 2k.

While I game my temps seem okay pending the game and setting I use for the game:

CPU: 45-60 c

GPU: 60-78 c

H100iv2: 35-41c

RAM: 45-50c

But even after upgrading the fans, the system is still very loud and the h100iv2 ramps up to 2500 RPMs randomly and starts throttling, don't know why it tried to go that high when the ML120 can only go 2000 RPMs.

I have tried my own custom curve (still does it) or use the quit curve (does the same).

The pump is set to Quiet since the only two sets I can set it to is Quit or Extreme, I cannot set it to balance. And when I set it to extreme the Fans for the h100iv2 read 0 RPM in iCUE but the fans still spin.

The only thing that seems to have worked is setting a fixed RPM for the fans and then a fixed RPM for my case fans, usually do 1400 for all fans. Just I would like to use a custom curve so it can be more if a set it and forget and I don't have to keep watching temps while I game or changing fans speeds.

One thing I was wondering was not controlling the h100iv2 from iCUE at all and connecting the pump to my motherboard AIO_Pump header then getting 2 Y-Splitters and connecting my push/pull fans to CPU_Fan and CPU_Opt and controlling everything in Asus Fan Xpert. As this experiencing with iCUE has been a headache (especially when it randomly flatlines and all temps just read the same).

Sorry for the long post. Any insight or help would be greatly appreciated.

You could try using CPU/OPT for control across the 4 radiator fans. There is nothing wrong with this from an electrical standpoint, however I am not sure how the fan will behave in terms of volatility. Despite clear "fan delays" programmed into both the BIOS and AI Suite, these are often ignored under certain conditions on CPU/OPT. I have not put it to the test on the Z370 platform, but this has not been an ideal control arrangement on the last several boards. Still, worth a try but with one very large caveat --- you can't run AI Suite and iCUE at the same time. This really isn't surprising considering the nature of the two programs, but we have seen users report not just jibberish data (expected) but also a loss of control or disappearing devices. Obviously that would be counter-productive. The half-way measure would be to move the headers to CPU/OPT and use the Advanced BIOS -> Monitor -> Q-Fan controls. It is a text version of the EZ BIOS graph, but that is where the delays hide. Also note, you can use standard CHA fan headers and it will stick to the script, but CHA headers are a bit precious with all these not so useful headers like OPT, AIO, and W_PUMP+. All three have strong limitations.

If you are running AI Suite now, you might want to stop, uninstall, run the Asus AI Suite cleaner, and see if iCUE behavior improves. I am not entirely sure why your custom fan curves are not following directions. Concurrent AI suite execution would be a reason. Another thing to try is setting your very last control point way out of reach. You should never get to 55C liquid temp (H100i v2 Temperature). Throw a dot there at 100%. That will blast and let you know if something has gone terribly wrong. The second to last point should be just above your highest normal coolant temp. So if thatis 41C, put it at 42-43C and set it a sound level you can tolerate. So if 1600 rpm is the most you can stand for any period of time, that's the speed. Gains from fan speed above the 1700-1800 rpm zone are very elusive on standard radiators, so there is no reason to set this too high. The lower curve points can go wherever you choose and again I would base the decision on noise. There is no significant cooling difference between 1000 rpm and 1200 rpm. If 31C is your baseline coolant temp in Summer, set that as the quiet idle speed 750-900 rpm or whatever you like.