90C is TjMax for that CPU but if you're not throttling or shutting down you should be fine. AMD recommends a AIO or other liquid cooling solution for the 5000 series CPU's. For example Corsair H110i GTX might go around $100 but it's worth every penny and should keep idle temps around 33c, loaded temps at 60c. The frequency is totally normal and rapid changing per core load is normal as well. Voltage is only that high for a short time per core load, using HWiNFO you will see the fluctuation of the power, temps, core frequencies aren't as constant as it appears.
You main concern is "is she gonna blow???" No, is the short answer. If you are running a liquid cooler, adjust your fan curve more aggressive. If you're using a very good air cooler, adjust that fan curve so it idles cooler and ramps faster to keep the temps a little lower. Technically speaking, it can run at that temp all day. The CPU will decrease speed and voltage if it gets too hot. Worse case is the PC will shut itself down.
If your super concerned, turn PBO off, it will still boost but not so aggressively and the voltage won't hold high for as long, therefore bringing operation temp down. If you set the scalar above "auto" to 10X, lower that or set it "auto". That CPU is a beast, you won't see a bit of difference in games by doing that.
Otherwise, those boost numbers are perfect.
"It worked before you broke it!"
