Moving parts are usually the first to fail on a computer. This is usually true of computer fans, of which there are usually two in most machines:

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one for the power supply and another for the CPU.
A sign that your computer’s CPU fan is failing is a change in the sounds that it normally makes.
If the fan starts to make wining, clunking or groaning sounds, it is a sign that the fan is coming to the end of its days. Once the fan stops working properly the CPU will not get the cooling it needs and will start to malfunction. So, we can say that a dying fan is a sign that your CPU will soon start malfunctioning.