The most important part of your laptop that needs to be clean is… the heatsink. Yes, heat is the “cause of death” for most laptops. The heat not only causes all components to expand and contract a little (as you turn it on and off), but will also reach dangerously high levels and make your laptop crash or shut down if the fan(s) and the heatsink(s) are clogged with dust.
All computers work a little bit like vacuum cleaners – sucking air form one side and blowing it out from the other. Unfortunately they don’t come with filter bags to catch all the dust and debris. After just a few months the fans and heatsinks are well coated with dust. If not cleaned, their effectiveness quickly drops and eventually goes down to zero when the heatsinks get fully clogged.
For desktop PCs this process is somehow slower and less noticeable as there is a lot of air circulating inside the case, hopefully with both intake and exhaust fans pushing it through. Also the CPU heatsink and fan are quite bigger and more powerful. There are also fans on the power supply, on the video card and probably on the chipset, for a total count of up to six fans making sure your PC stays cool. However laptops usually have just one or two smaller fans that have to do it all.
I would suggest a little experiment. Look around you for a lamp with an ordinary 100W light bulb. Now turn it on for five minutes and hold your hand about an inch away from it (be careful not to touch the bulb, it will scorch you!). Do you feel it? Yes, that is the heat generated inside that shiny new powerful laptop you just bought.
The cure? It’s easy: get yourself a can of compressed air and blow away the dust off the fan and heatsink. This has to be done every couple of months or after about 50 – 60 days of using your laptop. The compressed air is quite handy for the keyboard too, blowing away all the debris from between the keys. This is not a very well known fact, but it is the most important part of maintaining your laptop.
However if the heatsink has already been clogged, this won’t help. The compressed air will not be enough to unclog it. If you have never cleaned the heatsink and you had used your laptop for over a year, chances are that both the fan and the heatsink are clogged with dust and debris. The solution in this case is to remove the heatsink, clean it and install it back. This is best done in a laptop repair shop, as it takes quite a lot of experience and dexterity. One slip of the screwdriver may kill the laptop!
Some newer laptops have a special removable cover on the back for easy access to the heatsink. But most laptops have to be disassembled to reach it. Another problem is that the thermal paste between the heatsink and the CPU hardens with higher temperature, so if the laptop has been overheating, chances are that the heatsink is stuck solid to the CPU, making it very hard to remove. The process also includes removal of the old thermal paste from both the CPU and the heatsink and applying a small dab of fresh thermal paste, preferably silver filled for better heat transfer.
Another good overheating prevention is to ensure that the rubber feet on the bottom of the laptop are intact. Unfortunately they are usually just glued to the plastic and tend to fall off quite easy. They are very easy to replace and are available as spare parts for most laptops.
And lastly – don’t use your laptop while it’s on a soft surface, like bed cover or sofa. That will block the fan and the laptop will overheat. Try using something with a hard surface under the laptop, like a large hardcover book or a tray.
Simply put, heat is the biggest enemy of all laptops. By maintaining the cooling of your laptop at peak efficiency, you are doubling its lifespan.