If the keyboard and mouse don't light up, and the screen is all black right from the start, so you can't even go into the BIOS setup that's a serious hardware issue with the PSU or the motherboard. If it's the PSU it's a rather cheap repair. Find a repair shop and ask them for an estimate.
I was on my computer but out of the blue it froze while I was on mass effect Andromeda, it wouldn't ctrl alt delete, mouse, keyboard won't respond, so I left it for 10 min hoping it would come back, it didnt, so i turned the computer off, and when I turned it back on, I walked off came back 3 min later when I came back, it had a black and white checkerboard screen, so I turned it off again, and now this time its a black screen, and the keyboard and mouse aren't working/ light up. I have tried everything, I went to other forums that had this same problem but no luck so I'm making my own alert/ urgent question. I have let it cool down, took out all cords held down power for 30 sec to 1 min, went into the computer cleaned it took ram, graphics, all cords out ect and still no luck I have even done the resetting CMOS by talking out the round battery with all the cords out for 5 min and still no luck. This is urgent plz help

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