|You do not specify desktop or laptop, but I suspect that you have a build up of dust that is causing an overheating situation which is making the fan run faster to try to cool it down. On a laptop you would open ports and use a can of compressed air (computer or office supply store) to blow dust out through ports and vents.On a desktop you would remove the side panel and blow dust directly off components and out of heat sinks. Avoid making fans spin up extremely fast with the air can since it can lead to premature fan failure. Do NOT use a vacuum inside of the computer but wait until it is closed before cleaning up the area with a vacuum.|
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You have to be a little bit crazy to keep you from going insane.