Dust has been the cause of numerous problems that I have solved over the years. Some machines were very old and had never been opened up. Others just came from dusty work environments such as printing specialists or woodworkers. This dust could clog fans, block vents and ultimately cause components to overheat or become noisy. Whenever a machine would “just turn off randomly”, heat was often proven to be the culprit due to thermal safety cutoffs built into modern processors.
I solved many of these cases by making sure all cooling fans were held still (via masking tape or by holding them) and then carefully jetting out the offending fluff using an air compressor. I usually perform this outside, weather permitting. Some laptops and smaller items required disassembly in order to remove the finely-woven particles from their heatsink fins.
Many people were shocked by how much quieter their equipment ran after a thorough air jetting.