The first and most important thing you need to do when your laptop is overheating is to clean the fan(s) that provide(s) cooling to the CPU and graphics card. Over time, they build up layers of dust and dirt that slow them down and block airflow. Consult your laptop’s manual or manufacturer to find out how you can open the laptop to access and clean these parts.
Before you attempt to do any cleaning, however, follow these steps:
Carefully clean the fan(s) with a cotton swab dipped in a drop of alcohol. Make sure the alcohol has completely evaporated before you reconnect the laptop to the power. You can also use a vacuum cleaner to remove the dust and dirt that clocks up the fan(s). To prevent damage to the fan, do not let it revolve in the wrong direction. If you want to use canned air to clean the fan, arrest the fan by holding it down.
Next, you can clean the exhaust port by sucking out air with a vacuum cleaner. The exhaust port usually sits on the side of the laptop. It’s the opening that blows out hot air.
The intake grills are small openings that allow air to be sucked into the laptop by the revolving fans. They can sit on the sides or at the bottom of your notebook. To clear the intake grills, spray them with canned air.
Finally, you can apply fresh thermal grease to the interface between the CPU and its heat sink. Again, please consult the laptop’s manual or manufacturer to obtain instructions on how to disassemble these components.