How to fix an overheating notebook

The danger of your notebook overheating is very real  - but there are ways to keep it cool, or fix the problem if it starts to happen.

Inside a notebook (or any computer), the central processing unit generates heat when it's given work to do. Other components can also generate heat, like graphics cards and hard drives, but notebooks generally have more trouble with the CPU.

Processing a video, working with large images or playing games are among activities that can get your computer hot under the collar.

Notepads are often referred to as "laptops". In fact, using a notebook on your lap - or any soft surface like a bed or cushion - can lead to big problems further down the track.

The results might not be as dramatic as the picture above suggests, but rest assured it can be a costly and frustrating experience.

HOW DOES THIS HAPPEN?

One of the most common causes of overheating is the accumulation of dust, fluff, fur, fibres, hair and other particles - often known as lint - inside the notebook.

Those bits and pieces can eventually form an insulating mat that keeps hot air inside, which can lead to damage or even the complete destruction of your notebook.

You'd be amazed at how this evil lint mat forms over time. Look at the dust that accumulates on your mantelpiece after a month - or in your belly button after a day. Now imagine this getting into your notebook.

An aggravating factor is using your notebook on your lap or any soft, fibrous surface. While doing this, you can accidentally cover the air intake vent, which is on the bottom of most computers. This is not good.

Doing this not only drastically decreases the amount of cool air the computer can take in, but also increases the amount of dust and other particles sucked into the vents.

Some notebook designs are more susceptible to overheating than others. Have a look around a few forums and messageboards to get a feel for the usual suspects, but almost all notebooks will suffer from overheating eventually, as that evil mat builds up.

HOW DOES A NOTEBOOK COOL DOWN?

Inside your notebook, a fan sucks in air through an intake port. That air is then blown through a part called the "heat sink", which is basically a grille designed to have a high surface area for cool air to pass over.

Heat sinks are made from a metal that conducts heat really well, like copper, and is generally combined with an arm leading to a cooling plate sitting on top of your CPU (see big picture below).

There is normally some "thermal paste" between the cooling plate and the CPU, which provides the contact between the CPU and the cooling plate. This thermal paste can perish after a while and need replacing.

When the CPU heats up, the heat is conducted into the cooling plate and along the arm to the heat sink, which the fan blows through to dispel the heat.

If you feel the draft of air coming from the side of your notebook, you'll feel that it's warmer when you are making your computer work harder with video, games, graphics and the like.

HOW DO I KNOW IF IT'S OVERHEATING?

It's normal for a notebook to generate some heat when you're using it, but there are few signs when something isn't right.

I knew my notebook was overheating because the fan was going crazy and hitting mach 10 for minor tasks. It was like a smoker on a treadmill. The fan can be heard operating at high speeds as the computer desperately tries to cool itself.

If you do use your notebook on your lap, you may find that it actually starts to hurt or burn you after extended periods of use. You shouldn't have to take that kind of abuse.

Some notebooks have a temperature sensor inside which can be read by various desktop widgets or other software. Be careful what you install, research as always, but these can help you tell how hot it is running.

To get an idea of what is normal, look around for the normal operating temperature of your notebook's CPU - you'll need to find out what kind you have by right clicking your "My Computer" icon and selecting "Properties" - or choosing "About this Mac" from the Apple menu.

But basically, if it starts to get too hot, you'll know about it. The fan goes into noisy overdrive and the notebook gets abnormally hot.

MY LAPTOP IS BURNING UP - HELP!

First up, if you're not particularly tech-inclined, the best option is to take your notebook in for servicing by a professional. I wouldn't want anyone to mess up their computer trying to fix it themselves.

But if you feel up to the task, you can disassemble your notebook to clean out the dreaded lint mat, the fan and possibly apply some new thermal paste. You can buy the paste from electronics stores or online for a few dollars.

When disassembling your notebook, the most important thing is to research it thoroughly before you perform the surgery. Find out how to open it without damaging it - and keep all the pieces safe.

You may find there are YouTube videos that'll help, or you can read forum posts and guides. You also may need a couple of tools like a screwdriver and jeweller's screwdriver.

Once you find the fan and heat sink inside, you'll need to take them out and give them a good clean using a fine brush - your girlfriend's (or your) makeup brush is ideal (shhh...) or just use water and a rag.

You'll probably find a big, fat wad of dust, hair and other bad stuff blocking the heat sink. This is your primary enemy - terminate with extreme prejudice.

Clean the fan of dust and let it dry completely. The heat sink might need a wash under a fast-running tap to clean, or a blast of compressed air if available. Let this dry also.

To replace the thermal paste, remove the old paste completely using rubbing alcohol. Take your time to get every last sticky bit. Now carefully apply new paste - if you put too much on, it will bulge out the sides when you put the plate back on top.

Now reassemble everything in the right place, and listen as your notebook breathes a sigh of relief.

HOW DO I STOP THIS FROM HAPPENING IN THE FIRST PLACE?

All notebooks generally build up the lint mat, but you can help to slow down the process.

* You have to make sure that your computer can breathe through the intake vent. The best surface to use it on it a hard, cool, flat one - not your lap, a blanket or the carpet.

* Make sure that the rubber feet on the bottom of your notebook are still there. These give a bit of space between the surface and the vent. If not, source some more.

* Give it a rest. Using your notebook for long periods of time will cause it to heat up. Have a break - make yourself a coffee or something.

* Buy a cooling mat (pictured, right), which sits between the surface and the bottom of the notebook. These plug into your notebook via USB to power extra fans for good air circulation underneath.

* When buying a notebook, make sure you take heat production into account. Research, research, research. Forums are a great resource, as are your computer-nerd friends.

* Avoid using your notebook in deserts, at the beach, on the floor of a hairdresser or on the surface of the Sun.

If you've done all of these and it's still overheating, check out your notebook manufacturer's website for possible solutions. They sometimes have diagnostic tools which will check your fan for faults.

As a last resort, your BIOS could need an update. This is pretty advanced, and should only be carried out if you're absolutely sure of what you are doing.

Has your notebook ever overheated? Did you fix it, or did it die? Have you ever been burnt? Tell us your hot story!

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