My Windows Computer Won't Turn on, Why? (opens in new tab)

I am having a serious issue where my computer will not turn on at all. When I press the power button, absolutely nothing happens—no fans spin, no lights come on, no beeping sounds, and the screen remains completely black. I have already tried checking the power cable to make sure it is plugged in securely, tested the wall outlet with another device to confirm it is working, and even tried a different power cord, but the computer still shows no signs of life. I also attempted to hold the power...