The harmattan clogged your laptop's fan politely - clean it before it clogs the chip rudely

A laptop's cooling is a simple contract: air in at one edge, across a fin stack, hot air out - and dust is the one thing that voids it slowly enough that you adapt instead of noticing. Harmattan is the industrial version of that thing: the finest abrasive dust the household has to offer, drawn in by a fan that runs on purpose, binding with any humidity into felt exactly where the fins are thinnest. The good news is that the fix is fifteen minutes and a can; the better news is knowing the two ways the fifteen minutes ends worse than it started.

The symptom ladder, so you know your floor

• Fan that never stops, even at idle: the fins are partly blind; the fan compensates with duty cycle you used to never hear.
• The keyboard deck gets genuinely warm doing nothing much: heat that should leave through the fins is recirculating in the chassis.
• Slow only on your lap: fabric blocks the intake - but a clean machine only stutters; a felted one throttles, because it has no margin left. The lap is a stress test, which is why gamers' 'it slows on the bed' is a dust report.
• Shuts down under load with no warning: the chip's own emergency trip - the last polite rung. From here the options are a cleanout or a repair bill; the fan did not fail, the cooling was smothered.

The cleanout, with the two warnings

Work outdoors, machine off and unplugged, battery disconnected where it unclips without a saga. Open whatever panel the screws give you - most machines let you see the fan and the fin stack with six screws, and the service manual for your model is published by the maker, so you are not guessing. Then the first warning: hold the fan blade still when you blow. A spun-up fan is a generator, and forcing current backwards through its little cable into the board is the classic DIY heartbreak that the compressed-air tins' own cautions are written about; a toothpick against the blade solves it. Second warning: no vacuum cleaner at the board - the brush-and-nozzle static that a household vacuum is happy to make is exactly what chips die of; the can's short bursts and a soft paintbrush for the felt edge are the whole toolset. Blow in the airflow's own direction - out through the fins toward where the dust came from - in short puffs, until the puff comes back clean, and lift the matted beard off the fin face with the brush instead of trusting air alone.

When the cleanout does not fix it

Temperatures that climb straight back to old levels weeks after a deep clean are the paste's signature, not the dust's: the thermal goop between chip and heatsink dries into a crust over a few years, and in a hot climate it ages ahead of schedule. Re-paste is a legitimate job - but it means removing the heat pipe assembly, cleaning old paste with isopropyl, and a grain-of-rice reapplication with the screws tightened diagonally to even pressure - and on thin laptops the heatsink's clips and the board's ribbons forgive very little impatience. The desk's honest line: do the dust yourself, and if the paste is due, let the service that has the model's manual on its shelf do it, because the margin between a re-paste and a cracked glass panel is a screw you had no right to force.

The prevention tier, which is mostly furniture

Hard, flat surfaces - a hard serving tray is the lap-proof answer already standing in the kitchen. Outdoors during harmattan, the laptop closed and moved is better protection than any cover; keyboard lids trap dust against the keys in wind. One upside-down shake and a brush along the keys weekly through the season keeps the intake from what the room is made of; and the annual appointment that works is before the harmattan, not after the shutdown.

The verdict, as a rule

Idle fan screaming and deck warm means six screws, a toothpick on the blade, short bursts and a brush - the whole job, fifteen minutes, outdoors. If it still runs hot clean, that is paste, and paste is the one paragraph of this page you are allowed to hand to a professional. The chassis is a lung; during harmattan season, washing the lung is not a mod - it is housekeeping.