I also recently built a system with the 14900KF on an ASUS TUF motherboard and NZXT Kraken 360 cooler, and so far I haven't experienced any issues running everything at default BIOS settings (defaulted to 5.7GHz). I haven't seen temps above 70C yet, although granted I also haven't seen CPU load go above 40%, and haven't tried running any benchmarking software.
I'm curious about what you are using for cooling, as 90C at 5.4ghz seems way off compared to what I am seeing on my processor, but it could just be that I'm not pushing my processor quite as hard even with the higher clock rate.
I'm curious about what you are using for cooling, as 90C at 5.4ghz seems way off compared to what I am seeing on my processor, but it could just be that I'm not pushing my processor quite as hard even with the higher clock rate.