Need computer help, my computer broke

[Liam]

If your fans aren't working properly, it's probably running slow because the CPU is thermally throttled. If the CPU gets too hot it slows down, to prevent damage (fun fact, this is the main reason laptops are slower than desktops, they can't get rid of the heat fast enough).

I guess you should hold off on the windows reinstall until you figure out why the fans aren't working properly.