How to fix Laptop overheating problem

This is a very common problem, and one that I've had for a long time. But the solution is very simple. First of all, if you've bought your laptop after 2010 (with CPU i3 or higher), and an average graphics card, and the laptop starts overheating and running games slow, your issue is not a software one. The laptop should be able to do pretty much anything you ask of it...

Source of problem:

1) Partially blocked fan:
Although the fan is working, over time the dust and hair from your carpet etc can build up inside    it, and this greatly reduces its performance.
To fix this, open up your laptop and thoroughly clean the fans

2) Problem with the heat conducting paste:
This is a high heat conducting compound that is applied between your CPU/Graphics card and the heat sink. Overtime the material loses it's properties and drys out. so you need to replace it.

The material can be found in computer repair shops or on ebay. Look for "arctic silver".
To apply the paste you have to first clean the top of the CPU, where it is in contact with the heatsink. At the center of the image you can see the i5 processor with the cleaned top. On the right is the Geforce graphics card which hasn’t been cleaned yet (grey).
Also don't put too much paste, just enough to cover the surface. And it's very important to have both the heatsink and CPU points of contact very clean.

Now your laptop should run as good as new. Before this procedure my laptop overheated in a matter of seconds upon running games. Now it works like a breaze...
Also, if you are interested, the model of my laptop is the Sony Vaio vpcs117gg. For instructions on how to disassemble it, just ask in the comments.