Question High Temperature CPU Custom loop

[JusTye95]

Hi guys, I hope you can help me a few days ago I built my custom loop the problem is that the CPU (Ryzen 7 5800x) temperatures are very high at stock setting then pbo2 active the cpu reaches 85/86 degrees limiting a lot the performances the stress test i did is cinebench (i ran it many times) and checked the temperatures with hwinfo before assembling the loop I opened the CPU block, cleaned well and reassembled (It was not dirty but before creating a new loop it seems right to clean everything) the thermal paste I use is Artic MX5 applied to X Before creating this loop I had created another (more basic) one and the CPU temperatures were much lower. what am i doing wrong? I can not understand. I have had a lot of problems with air bubbles these days, but it seems to have solved it, but I don't think that's the problem my loop is made up of 2 360mm radiators I post the photos of the first loop and the second loop
1st (good temperature) https://ibb.co/XjWXCNH
2nd (bad temperature, current configuration) https://ibb.co/h1rdgdp
Edit: PBO Auto, Power limit Auto, Boost clock +150, Curve -15 Cinebench crashes, and very high temperatures

https://imgur.com/SJ8eCsW

Edit2:
I disassembled the water block, I think everything is ok, is the contact of the thermal paste good?
https://ibb.co/mFFHBx3

20211118-180725 hosted at ImgBB

Image 20211118-180725 hosted in ImgBB

ibb.co

View: https://imgur.com/SJ8eCsW

 

[EuphoriaNS]

Is there a chance that the heating of the house has started and the problem is the radiator behind your PC?