Question Upgraded PC build, worked for 2 days and now I have no post or display.

Apr 20, 2020
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Hello, I’m new to the forums. I recently upgraded my mother board, Ram, and cpu to my PC. Everything was running fine for 2 days. But when I went to get a snack and came back I saw my screen go blank right in front of me. So I tried another hdmi cable and no display. I hooked up the Nintendo switch to the pc monitor and the monitor works. That’s when I tried to turn it off with a hard reset but I noticed that my PC won’t turn off when I do this. I have to switch the power supply off in the back to turn it off. When I turned it back on I had no beep his time to let me know that it post and was good to go. My friend let me try his power supply to see if that worked. And nothing. He tried his pc in the same wall outlet that I was use if and his pc turned on just fine. I tried using my old graphics card and nothing. I tried using my friends graphic card and nothing. I checked to make sure all the cables were properly plugged in 3 times now and still nothing. I’ve tried running it with one RAM stick in each port and still the same issue. The motherboard fan still spins along with all the other fans connected. The RAM light turns on in every port. All led lights turn on. I was missing one standoff screw in my tower. My friend let me borrow his and still the same issue. Is it my cpu? The motherboard and cpu and ram are brand new.
Here are my specs.
Motherboard: gigabyte x570 UD amd ryzen 3000 desktop ready Am 4 ddr4.
CPU: Ryzen 5 3600
Gpu:1660 ti
Power supply: evga 500w
Ram: crosiar ddr4 32gb
Ssd 500gb
External Hd 1tb