Question PC boot up takes an eternity. Large blue/red square appearing at the startup ?

[randomnumb3r2000]

VIDEO LINK: https://streamable.com/89vz0c

Does anybody have a clue what might be causing this problem?

B450 TOMAHAWK MAX
SAMSUNG 860 EVO 500 GB
AMD RYZEN 5 3600
AMD RX 580 8GB
G.Skill Flare X 16GB DDR4-3200MHz

 

[rgd1101]

brand and model of the psu?
check cpu/gpu temp?
how full is the ssd?

 

[randomnumb3r2000]

FORCE SL-X650-EPS
https://www.skroutz.gr/s/23282993/Supercase-Force-650W-Full-Wired.html

Temperatures are okay.
I still have 200 GB free on SSD, although this problem has been occurring since I have installed windows on it.

 

[randomnumb3r2000]

I would still appreciate if somebody could give an idea why this might be happening