It pains us to say this (considering the amount of time and effort put into this PC) but this passive build just doesn't work. The CPU cooler is way too small for the very hot i7-8700T, the Raijintek Morpheus is not really designed to run passively, but most importantly the Lian Li case is not used properly. Hot air is less dense than cold air so it wants to float upward, not laterally.

Source: reddit