It's usually a failing fan which means things are getting hotter, slower.
Time to pop the lid and get out the canned air too. Failing fans can lead to failing machines so fix that now before it costs even more.
My computer has started to run slow and my power supply is making noise when i start the computer.Is it possible that my power supply isn't supplying enough power to other components like the GPU or the CPU and that is causing my PC to slow down?

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