Authored by: Support.com Tech Pro Team
Fan are used to help keep the inside of your computer cool. If you are hearing loud fan noise, this could be the result of the following.
This guide will help you to identify the cause of your fan noise and provide a resolution to your issue.
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Most laptop computers have easy-to-spot ventilation areas where heat is expelled from while they are in use. Your MacBook computer has a less-obvious ventilation area around the rear screen hinge.
Ensuring this area is free of dust, debris, and other blockages is the easiest way to make sure your MacBook is able to expel heat in the way it was designed. Use compressed air to clean around this ventilation area to help keep your computer running cool.
There may be occasions when a piece of software on your Mac will crash or become unresponsive and take up too much CPU or memory. The best option is to go to the Activity Monitor and see what’s causing the congestion.
Activity Monitor shows the processes that are running on your Mac, so you can manage them and see how they affect your Mac's activity and performance.
Many MacBooks have both an internal graphics processor and a discreet graphics processor. When automatic graphics switching is enabled, your MacBook will switch to the internal graphics processor. When this happens, it can save power, but also puts an extra load on your CPU causing it to heat up. You can turn this option off to use the discrete graphics processor which may cool your CPU temperature but use more power.
Not all MacBooks will have this option available.
If you have performed all of these steps and still have loud fan noise, then you may be looking at a internal hardware issue.