PC booting errors.

[Garthoro]

I made a post about 6 months ago but I kinda forgot about it and never answered it. The problem is I've been having some booting problems in my computer. I built this 7 months ago and started having problems about a month after building it, components are: I7 7700 (currently using stock cooler), MSI M7 Z270, MSI 1080 Oc x 8gb, 16gb Corsair ram (2 sticks 8gb/ea) and a 1TB WD Blue HDD. Since I made that post I've been having some booting errors once every 2 weeks approximately. In all errors the pc boots, cpu fan working, ram LEDs turning on but nothing shows on screen. The MOBO comes with debug lights and a debug code display (where the cpu tempetaure shows when the computer boots on), in the debug lights I've seen the DRAM and CPU turn on, the first time I got this kind of error the DRAM was the one that turned on. Also when this kind of thing happens on the debug code display appears mosty frequently E0 OR 9A, and sometimes I think 9C has appeared too but I'm not that sure about this. This photo is the page of the manual that explains the debug codes on the MOBO.
I had a different problem today for the first time, I went out for about 1 hour and left the computer turned on, when I came back the computer was off, I thought maybe my brother had turned it off or something like that, when I turned it on it started turning on and off looping (same as before, CPU fan, RAM and GPU leds working and then it stopped, approximately when fans stopped moving it turned on again) it kept doing this for about a minute until I switched the PSU off.
If there's anything you guys need just comment, thanks so much for reading.

 

[Garthoro]

I forgot to add this also happens sometimes when I suspend the computer when i try to use it again the same happens, computer seems to be working but has the error lights on and screen isnt recieving anything