How Laptops Generate Heat

• Laptops are not designed to generate heat; instead, heat is a waste by-product from the use of electronic components inside your computer. All electrical devices have some resistance to the flow of electricity through its wires, and this resistance converts electricity to heat. The hotter an electrical component is, the more electricity it is wasting in the course of achieving its desired functionality.
  
  In some machines, this waste heat can be put to good use, such as diverting the engine heat from an automobile into heating the interior of the car. But it's fairly rare to use a laptop in temperatures where you would want it to heat your lap, so laptop manufacturers instead design their computers to ensure that heat is radiated outward from the interior as quickly as possible. Excessive heat can damage chips and other components, so efficient heat engineering is crucial to the durability of the laptop.
  
  

Reducing Laptop Heat Output

• There is a one-to-one correlation between power consumption and heat production; the more power your laptop uses, the more heat it will generate. The only way to reduce the ratio of power used to heat generated is by replacing the laptop; some desktop computers can improve this ratio by swapping out internal components for more efficient parts, but this option is rarely available to laptop users.
  
  All of the tricks you may have learned to prolong laptop battery life will also apply to lowering heat production. Set your CPU to run at lower speeds if you are not using computation-intensive software. Corollary: avoid running computation-intensive software, such as large spreadsheets, video editing software and media conversion tools. Copy files off of DVDs and CDs to your internal hard drive so you don't have to run that drive, and consider converting your movies to lower-resolution versions. High-definition movies require a lot of computer horsepower, so a little blurriness will mean a cooler laptop.
  
  

Increasing Heat Circulation

• Your lap is a poor heat dissipator; your body warms the bottom of your laptop to nearly 99 degrees Fahrenheit. Resting your laptop on a cool surface will draw heat out; marble and metal surfaces are excellent for this because they efficiently conduct heat as they tend to stay at room temperature. Laptop cooling stands can also be used to increase air circulation under your laptop, sometimes with the use of powered fans; in a pinch, use a sturdy laptop sleeve as a lap desk with a built-in air pocket.