Here are Tools & Chemicals you need for have a clean computer CPU casing.
Soft cloth, Computer cleaning fluid, compressed air, safety glasses, pre-treated computer wipes, vacuum cleaner, and special cleaning attachments.
It is best to store the CPU off the floor, on a solid surface to minimize dust and permit proper cooling (carpet will not allow for airflow beneath unit). Vacuum all cooling slots. Do not use compressed air on these openings, as it moves large amounts of dust inside the CPU, which is akin to pouring fine sand into the processor. Conversely, if you are trying to kill your computer, this, water, and blunt impacts are the quickest methods.
Keeping the vents clean maximizes airflow for cooling, which is very important for the longevity of the CPU. Processor failures are most commonly associated with the expansion and contraction of connections and components. By keeping the overall operating temperature low, the extremes between operating and shut down temperatures is reduced, lowering the magnitude of the cycles, and increasing life span. Wipe down the casing with a soft cloth dampened with a specialized computer cleaning fluid or plain water. Never spray any cleaner directly onto your office equipment. Always spray the cloth and wipe the equipment.
If you feel you need to remove the casing and clean inside, use compressed air only. Take care to direct the air out and away from the casing so you don’t drive the dust deeper into cracks and crevices. A slightly errant brush, cloth, or vacuum can cause permanent damage, and without even touching the boards, a zap of static electricity can destroy a processor. Check your warranty before taking any office equipment apart. If you remove the cover for the casing you can wipe down the inside of the casing before closing the and securing CPU etc. These are some basics for having a clean computer.