My friend just gave me a PS4 that was defect so I can try to fix it… But I am kind of confused.
First of all, the PS4 was not displaying anything, so I started safe mode and there was a lot of red (non static) pixels. I then changed the resolution to 480P, and it worked, but the dots where still there.
I then came across the idea of resetting the whole PS4 (without changing the OS), but nothing changed.

I tried to change the cable, the HDMI port , and the monitor, but nothing changes.
I have the capacity to replace the HDMI port of the PS4, should I do that ? Or is there another solution ?