I bought my son parts to build a pc and a friend who said he had built many 10+ before helped us build it. her are the specs and is there anything we need to do. we did flash the bios per friend. sorry don't know much but can google and read anything.
it all runs fine but the monitor stuff says it's 88-90C and the kids say that is too hot.
More than likely you have an issue with the water cooling setup. Could need to be bled better. Or have an issues with thermal compound or mounting pressure and or consistency. Could be the orientation of the hoses to the radiator, for instance if the radiator is vertical the hoses should be at the bottom. Could be not enough air hitting the radiator so a fan problem.
There are a ton of how to videos and very likely even one for your model cooler on You Tube. I would search for one but even one that is a similar setup would be fine to watch. Should give you some good ideas on what to check.
I personally went back to air cooling as I find a good air cooler to be much cheaper and less problematic than most water setups and in many cases they are even better cooling than a lot of the cheaper water setups.
Also the support department for the company that made your AIO could be very helpful in troubleshooting where the issue is. So I would ask them for help too.
Run HWINFO
Check your temps and fan pump rpm
Sounds like your cooling is not cooling anything
Unfortunately with 5800X, that's the normal temperature. 5800X runs hotter than the other 5000 series.
The only thing you can do is to negatively offset the Vcore by 0.050~0.100v
One thing I noticed, it seems like PBO is always on with 5800X even though it's off in the bios. I've tested this theory with a 5950X I borrowed. I was able to see the temperature differences between PBO on and off.