I think my computer is teh broken

i have to post this on our old computer because the other one won’t start.
It was on this morning, and i left it on when i went to uni for a few hours, and when i came back it was still kinda on (the fan was whirring, sounded like everything was fine) but it wouldn’t wake up when i moved the mouse…the screen was off. Also, the keyboard wasn’t powered because none of the lights were on.

so i had to turn off the main power switch at the back, and now when i turned it back on and pressed power, it plays this audio clip saying “system failed cpu test” or something like that… just over and over from the speakers.

seriously, what the?