The evolution of computers from ENIAC to the extremely portable laptop has made computing an everyday task. The then used vacuum diodes became extremely heated that diodes had to be replaced after every hour or less. With a little improvement, lifespan was increased to about a day or two but heating was the major obstacle being faced by computer engineers.
Today we have desktops and ultra-thin laptops, which also use processors which are now integrated ones. Every electronic equipment produces a noticeable amount of heat so does the processor. Not only processors but the motherboard along with the GPU(graphic cards) produce a good amount of heat.
Computers are equipped with a variety of cooling equipment, like a fan, to disperse the excess heat generated from electrical energy, and a CPU fan is used exclusively for cooling the processor.
2.Active or Fan cooling.
Mostly it is the fan cooling which is used in most of the computers, where the components like processor get heated at a fast rate. Fan cooling is performed in conjunction with an Aluminium Heat Sink because direct cooling cannot be performed since heat emitted is more conductive than radiative. To understand how this works:
Heat Sink Fan: The aluminum heat sink fan is a cooling device that works on its own to efficiently draw heat away from the components into its large surface area to transfer cooler air into its fin-like aluminum structure. This cooling device works in unison with all the major components of the computer.
The fan is attached to this fin-like structure and improves the transfer of hot air by pulling the hot air from the electrical heat generated by the components and pushing in the cooler air between the aluminum fins, thus keeping the processor cool.
Talking of the passive cooling there is no fan but only a heatsink alone.Passive cooling is widely used in all types of electronic circuits to dissipate component heat, heatsinks thus preventing burnout of crucial components like MOSFETS.
But what happens in a laptop??
Laptop cooling is completely different from desktop CPU cooling. Instead of using big heatsinks with fan. They use heat-tubes which are made of copper which is a good heat conductor.
To increase the conductance of heat from processor to heat-tube thermal grease is used which is a kind of paste. All the major heat producing components are in contact with heat-tube which is then linked to a cooling fan which forces out heated air from the heatsink-tube, making the processor cooler and helps in better performance.
Liquid cooling is also used but it is not in common and used in bigger computers.
Good processors with better operating speeds can withstand up to 100º C. Some can up to 120°C but that is the last limit, for safety reasons your computers gives you a warning and shuts itself when reaching 80° C or more.
Computers being the most important devices in our daily life, it is very important to maintain them properly and check for their proper operation. Temperature is one condition that is quite important for the maintenance of these devices. So one should have proper knowledge of how the technical aspects of these cooling systems in computers and laptops.
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