Dirt and dust can damage your PC and hurt performance. Fight back

This article appears as part of the April 07 issue of PC Advisor, available now in all good newsagents

It's that time of year again. Time for a spot of spring cleaning. It's not much fun, agreed, but if your computer's insides are dirty then it's probably suffering a nasty case of sluggish performance.

The Hassle: My PC overheats toward the end of the evening, even though my office is cool.

The Fix: Your PC's case is almost certainly full of dirt, dust and other yukky stuff. If you have a pet, the system is probably loaded with hair, too. And I'd wager that it sits on the floor, under the desk, gathering dust. So here's what to do.

Before opening the case, unplug the power cord and any other cables. Once opened, touch any metal part of the case to discharge static and ensure that you and the inside of the PC are at the same voltage.

You should repeat this process every time you touch the PC's innards. Start by removing the foam filters on the fan vents. Gently clean the filters in a mild solution of washing-up liquid and cool water – but remember to ensure that the filters are dry before you replace them. Alternatively, buy a foam air-conditioner filter, cut it to size and replace all the filters.

Remove most of the dust by vacuuming the fan vents from the outside of the case. However, be very cautious about vacuuming inside the PC. You should avoid touching the motherboard and add-in cards. At most, suck away the dust lying on the base and on the bottoms of empty drive bays. Avoid using brushes on components.

If the weather is dry and not too cold, take the computer outdoors and use a can of compressed air. I bought a can with a foot-long hose attached, but you can buy tubing at any hardware shop. Using a hose means that you can effectively clear dust away throughout the case, while holding the air can upright. Spraying from a tilted can causes a wasteful blast of icy liquid propellant – and enough of a temperature change to damage sensitive components.

You may be tempted to spin the fan blades of the heatsink with a gust of air to clean them. Don't. The fan can't take being spun at speed. Your best bet is to hold the fan and then blow with the air. Next, you will need a cotton swab, soaked in a weak alcohol solution, to finish cleaning each blade.

But even more important than cleaning the fan is to carefully blow the dust from between the blades of the heatsinks. Place the nozzle between the fan blades and along the open sides of the heatsink until no more dust flies out. But whatever you do, don't use the sort of air compressor that you would use to fill your tyres at a petrol station. These often contain a mix of oil and water.

Finally, raising your PC from the floor, even by just a few inches, will reduce the amount of dust that gets sucked into the vents. You should be able to pick up a small furniture dolly from that hardware shop.