EightBitRanger

I was able to connect my AX860i to my old H100i with the digital interface cable and have both show up in Corsair Link but unless I'm missing something, I can't find a place to connect it to on the H100i Pro. Is that functionality no longer around on the newer cooler models?

You were right. The cooler definitely wasn't running how it should have been. I got an H100i Pro like you had suggested and after running Intel's stress test for 5 minutes at 100% load, core temp didn't top 45c and pump speed was around 2700 rpm.

Thanks for the feedback, that's good to know.

I'm not sure if my 5-year old H100i (CW-9060009-WW) is starting to wear out on me; lately I've been getting ridiculously high temps even at idle (thermal throttling at 100c even at idle). If I end up replacing it with another Corsair, how much difference is there between that one and one of the newer H100i's like the CW-9060025-WW, CW-9060033-WW or CW-9060039-WW? RGB is of little importance since my case is fully enclosed without a window; I just need something to keep my i5 9600k cool.

My CPU has been overheating lately too. My first instinct was to suspect my AIO was starting to fail since nothing else has changed. Immediately after booting up, core temp of 41c, fan speed at 1215rpm and pump speed at 1307 rpm on quiet. After running a CPU stress test for 5 minutes, core temp was throttled at 100c, fan and pump speed both abut 2650 rpm on performance. Even after letting the rest and cool down for 5 minutes afterwards, temps had only dropped about ten degrees keeping on performance.