You would start with a new PSU but I've seen such failures take out every part in a PC. Let's hope it only fried the PSU and maybe the motherboard.
Ok so let me tell first what I did to my PC. I don’t know if these are all connected but let me provide it anyway. So first is I turned off the automatic update of windows. After that I noticed that everytime I open my PC, the date and time are not updated so I adjust it manually. It all got better, however, just last week, I didn’t turned off my computer for 2 days and I had problems with watching videos. When I click one video it will not show up and I need to wait for about a minute or two for it to play. When I shut it down, it displays the blue screen with Shutting down message on it. i waited for about 3-5 minutes but it is not turning off so I pressed the power button for a few seconds and it shut down. So after a week passed, today, I tried to open the cpu but it is not booting up. No fans running, no lights except for one steady yellow light on the motherboard. I tried bunch of suggestions in another forums but nothing helps. And then I fiddled with the red thing at the back that says 115v and 230v I slid it and choose 115v idiotically and after I put the power cable, the thing which I believe is the power supply, got Fried and there’s smoke and the yellow light is no more. So now I don’t know what to do, if I ruined my cpu! Did it affect all the hardwares like the motherboard? Should I replace my cpu or I can still save it by replacing the power supply?

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