Hi. My name is Kacper, I'm from Poland. I'm new here, it's my very first post and I'm very sad I have to ask for help. I just built a PC recently.
Let me start with giving the list of all components:
Motherboard: ASUS ROG Maximus XII Hero.
CPU: Intel Core i9 10850k LGA 1200.
Cooler: Arctic Liquid Freezer II 360 with Arctic MX-4 thermal paste applied.
RAM: 32 GB (4x8) 3200 Mhz (set as XMP I profile).
GPU: Zotac 1080TI AMP! Extreme (hoping to get 3080 soon).
Case: ASUS TUF Gaming GT501.
System: Windows 10 Home x64, update 1909.
BIOS version on the mobo: 0901.
So, idle temperatures seem to be fine, around 35* to 40* Celsius.
Problem starts when I play demanding games, I tried two at the moment, Red Dead Redemption 2, and HITMAN 2.
In both games average temperature was at ~90* Celsius, with max going even to 103* Celsius.
After about 20 minutes of RDR2 I had temporary thermal throttle on all 10 cores.
I know nothing about BIOS and overclocking in general. I can tell I only set up XMP profile to boost my RAM to 3200 Mhz.
I have no idea what voltage and speed it should have, but temperature is definitely too high.
Had i7 8700k before and maximum temperature in RDR2 was about 85*.
I'm super scared already.
Here is the screenshot I did from HWMonitor right after closing the game

During the gameplay I experienced graphics glitches.
Not sure if it's important but Arctic Liquid Freezer II 360 has only one plug, going out of water block. I plugged it into CPU_Fan header. Maybe I should've plugged it somewhere else?
I believe cooler is installed properly. I also applied thermal paste using single drop method, about 0.4 gram of paste was used. I definitely removed plastic foil from the cooler. Air flow in the case seem to be fine too: 3 intake fans on the front, 3 exhaust fans on AIO radiator, and 1 exhaust fan on the rear of the case.
I would be very grateful for any support. Best regards.
PS. If I posted this thread in the wrong place, kindly please move it and don't hate me.