[brobot182]

I have almost the exact same setup as you: same CPU cooler, same CPU, and the pro WiFi version of the Z390. However, when I’m doing a long-running clean build that uses the 16 logical cores, the temperature for each core gets up to 80 C. Any thoughts why that would be?

[Macha]

Is your environment 10C higher than OP's? Most reviews compare coolers in terms of the temperature increase over background temperature to control for this.

80C for a 9900k under sustained high load would not concern or surprise me. It's a high end power hungry CPU. 100C is the cutoff temperature so maybe more cooling might help it turbo more but I doubt you even get throttling at 80C.