Specs:
CPU: Ryzen 2600
GPU: Radeon rx 570
PSU: Thermaltake 600w
Motherboard: Gigabyte b450m ds3h
RAM: G.Skill 16GB stick 3200 mhz
Also have western digital 1tb HDD and an m.2 ssd 128gb (Windows is on my HDD)
So I built a gaming pc a little over a week ago and everything was operating fine. My games were running well and everything was good. A few nights ago, I gamed rainbow six siege for about 2 hours and then played a game of Apex Legends. My system didn't seem to be overheating so that doesn't seem to be an issue, but I'm not 100% sure. Anyways, I had left it on and used my browser for a bit and then left it (I don't remember if I put it in sleep mode or just let it idle all night). When I went to use it the next day, I pressed the keyboard to activate the screen and no signal was coming up. It was as if nothing was connected to my screen. So I made sure my PC was on and it surely was, so I went to turn it off.
I held the power button for 10+ seconds and nothing happened. My PC was running but it would not shut off, so I used the switch on my PSU as I tried for a few minutes and couldn't get the power button to work. I turned it back on and my screen would get to its normal GIGABYTE screen where I can press DEL for BIOS, F9, etc.... and it would say "Starting Automatic Repair" and have the circle go around 2-3 times before losing display. I notice that when I start up my PC, everything works like my case fans, my cpu fans, and my gpu fans. As soon as my screen goes blank, my case fans stop working and so does my GPU fans, but my CPU fan keeps going.
I have tried using a different power supply and graphics card and nothing changed. I don't have an integrated graphics card so I used an old EVGA GTX 660 ti. I also took out my HDD and downloaded windows onto a flash drive and tried to install it through my SSD, but all I get then is the windows logo and it just sits there, no loading circle or anything. I have gotten it to the point where the circles spin and says "Starting Automatic Repair" but it still crashes like stated before. These different reactions would come from changing my boot priorities in BIOS, but either way, I get nowhere.
Also to mention, when I load up BIOS, everything in my system seems to be working, but as soon as I exit, it goes back to that GIGABYTE screen and my fans stop operating and I lose all display to my screen. When I am in BIOS I can turn off my PC with the power button properly, but as soon as I lose display, I can no longer turn off my PC with the power but and have to use the switch on the PSU.
I am really just looking for any help with identifying what the problem is. This is the first computer I have ever built so I don't have much experience with failing parts. As far as I can tell, the issue lies with either my CPU, RAM, or motherboard, but I don't know if that is an accurate thought or not. I have looked into resetting my CMOS but I have yet to do it and am still unsure of how exactly to do it. Everything was working well and fast for over a week and now I am somehow here If anyone can help, please let me now!!