If you don't clean the CPU fan, it could break. If it breaks, the computer may overheat. The easiest way to clean the CPU cabinet is to use compressed air.
Steps
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Step 1. Turn off your computer
Unplug the power.
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Step 2. Place the PC on an antistatic mat on a table
For added safety, you could also wear an antistatic wristband. You will prevent your body's electrical discharges from damaging your PC.
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Step 3. Open the PC case following the manual
Some PCs open with a screwdriver, others have buttons to press.
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Step 4. Place the compressed air at least 6cm away from the CPU fan
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Step 5. Spray the air in small strokes on the grille and metal filters
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Step 6. Spray air on the fan blades
To remove more dust, spray the air from different angles. Make sure you don't touch other devices inside the case.
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Step 7. Put down the compressed air and close the PC
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Step 8. Clean the PC case with a damp cloth soaked in soap
Dry the surface well.
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Step 9. Use a cloth to clean the cables while they are unplugged
Dry them with a soft cloth.
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Step 10. Reconnect the cables and turn the PC back on
Advice
- While cleaning the CPU fan, take the opportunity to clean the motherboard and its surroundings.
- Reduce the dust entering your PC by cleaning your room regularly. Also try to cover the equipment to keep the dust out.