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Cooling down your PC

A Personal Computer System or a laptop needs to cool down once it has been running for some time as it has a natural tendency to get hot after a while. There are several ways of cooling a PC down like Passive Air Cooling, Passive Water Cooling, etc. Similarly, there are lots of components that need cooling in a PC like a Graphics Card, Processor, Northbridge - Southbridge, mosfets etc. Obviously, it can be controlled by changing & placing different components: placing the fans, increasing the number of fans inside the cabinet, choosing the right system unit etc. Essential elements will automatically be looked after such as application of thermal paste, perfect cleanliness process etc.

Cooling down your computer, whether laptop or desktop is essential. At some point you may be required to change the fans and radiators. But the choice is vast and the most expensive is not always good. I will detail in this article the different cooling methods and their interest.

The different methods of cooling a PC

So now I will go through the different ways of cooling your PC.

The passive air-cooling

The passive air-cooling is simply composed of a radiator, the same as described above. The advantage of this system is it is perfectly silent 0dBa.

The passive water-cooling

The passive water-cooling system uses natural conductivity of the box enclosing the radiators (which are there to receive the water heated by the various components on the circuit Water-cooling). The only manufacturer (to my knowledge) is the east Water-cooling Zalman passive. The advantage of this system is that it is silent. The noise may come from the pump, but the manufacturers make sure that the pump is also silent.

The cooling water assets

The cooling water asset is built the same way as the liabilities, but the heat collected by the radiators is directly expelled by fans on the radiators to achieve a delta nearest possible zero (delta °C = temperature of component - ambient temperature). It is often used by overclockers to move away and can be rendered silent by choosing the correct components.

The various components to cool your PC

Your computer is made up of several components that support all temperatures higher or lower, and therefore need to be cooled.

Graphics card

The graphics card is an essential component of the computer. But it is equally essential to keep cool.

There are two methods: the passive (fanless) and active (with fan).

The passive systems are widely used on graphics cards for entry. They are generally made of a plastic radiator, small enough to be integrated into the micro housings or a media centre.
They are also present on some high-end cards. Typically, heat and leave the GPU go behind the card to remove heat from the air, naturally present in the cabinet. When the case is not sufficiently ventilated, the temperature of the GPU is likely to rise... the PC will cut off if the security options on the temperature are activated and eventually burn if such security is disabled.

Active systems are the most widespread and cover all ranges. They always consist of a radiator which is attached to a fan. The effectiveness will depend on several criteria:
  • The diameter of the fan
  • Speed of rotation
  • Its design
  • The materials used for the radiator
  • The size of the radiator

The diameter of the fan, coupled with its speed (and the design of the blades) will define the flow of air that it is able to generate. The materials used for the radiator will determine its effectiveness and the size of the radiator + fan efficiency surface will therefore be responsible for heat dissipation.

To replace them, consider the compatibility for this; I refer you to the site of the manufacturer from which you want to buy your new system.

To replace the base system must take into account the place you have. You may encounter problems if you intend to mount a multi-GPU, or if you have a micro case. You can, of course, change your original system of a passive with an active or save on your GPU Watercooling!

Watercooling: requires heavy investment and waterblocks are rarely consistent from one generation of cards to another. And again, it will reflect the size factor, but also the power of your pump. If you buy a low-end waterblock, you'll have more chance that the water is slowed down coming into the waterblock. A high-end system will be optimized to facilitate the flow of water for cooling.
Finally on the graphics cards, you need to cool your memory. In general, the equipment needed for cooling is provided. Otherwise, I strongly recommend to buy one.

The processor

The processor, also known as CPU (Central Processing Unit) or for intimates Proco, is an essential component of your computer. As you guessed, it is to cool it.

The fan provided by Intel or AMD is rarely satisfactory when attempting to operate in silence or you want to start the overlock.
We must therefore replace it! Again, there are different methods:
  • The Watercooling
  • A passive cooling
  • An active cooling

Again for Watercooling, is an important investment to make. It takes a quality waterblock to prevent the flow of water from slowing down.

Then, the passive cooling. Overclockers, read the following paragraph. The system, completely silent, because no fan is recommended when you want to work in silence, the most comprehensive and preferably with a fairly large box (18 cm minimum) and well ventilated. The choice is difficult and many manufacturers started in the race. Some excellent systems made by Thermalright, Noctua and Scythe (not to mention them all) will be sufficient for liability. But beware! Before buying, read tests without radiator fan and ask about the compatibility of the socket, if your case is large enough and sometimes if your motherboard is compatible. But we must remain vigilant (e) in the early days with this kind of system: a processor with a high TDP and pushed to its maximum load will overcome the radiator.

As for the active system, it is possible to have one and work in silence. Attention at this time to dBa (<20 dBa for silence). But overclockers will be very satisfied. With the right system, it is possible to mount the processor to a relatively high frequency. It is therefore advised that overclokers have a large box to accommodate radiators. In general, passive radiators go from good to fantastic once one or more fans are added. Again, the brands are: Tuniq, Noctua, Thermalright (again, I will not name them all). When buying, we should keep the processor socket, the size available on the motherboard and the width of the housing.

The Northbridge, Southbridge

The cooling of the Northbridge and Southbridge is most often provided by both systems (liabilities):
  • A low-end radiator aluminum
  • A circuit radiators connected by heatpipes

If you are not a (e) bit (e) of the overclocking, it is often useful to change the system since the change of flow pipes including the radiator to change the Northbridge, Southbridge and mosfets!
But when you love it, the temperature of Northbridge is very important. All current (and successful) are passive, but it is sometimes advisable to add a fan. The radiators are shaped to turn the most powerful and it takes time to be careful where you have a Crossfire or SLI: the radiator can interfere. The alternative, less expensive, takes the form of a small radiator and copper is a good alternative to low-end aluminum. You should, of course, check the list of compatible motherboards at the site of the manufacturer of your future radiateur Northbridge / Southbridge.

The mosfets

The mosfets are located near the CPU socket are semiconductors that have the annoying habit of swell or explode when they heat too. These symptoms happen more often when you overclock without taking precautions, it is imperative to ask (if not) or to change the system dissipation overcloker when you want or you change the radiator Northbridge and that these two components are linked by a heatpipe.

And as usual, the mosfets can be integrated into a circuit Watercooling!

The Hard-drive

Some hard drives have a nasty tendency to heat much more than we would like. It is therefore possible to incorporate a water cooling circuit, to the hard drive into a passive system consisting of a flat radiator and heat-pipes to dissipate heat, or a passive system with fans to enable more rapid dissemination and efficient heat or simply a system with more fans to ask about the disc.
Once this integrated system, hard drives will take more space and some may no longer fit in the usual 3.5-inch bays, so it will stay at the top of the housing in a 5.25 inch bay.

Organize the cables and hardware in your casing

Good organizing of your casing can save a few precious degrees and reduce noise in some cases.

Placing different components

In Physics the cold air falls and hot air rises. We must therefore place the components accordingly. We recommend placing the disks at the bottom of the box, near the fans honey combs, not in the middle of course, but at the top of the fan so that air passes under (or on) the hard disk. The graphics card, processor, RAM, hard drive to change their place! As for food, which also releases heat, it will depend on your case. Cases in which food is at the bottom are generally "better" because the lack of food at the top of the box gives more room for a suction fan at the top of the case, for example. Regarding the CD, whatever! The heat is very low because they are not in constant demand. We must also try as much as possible to properly store your cables. A cable that goes into a fan and is the immediate halt of the system! A cable on a ventilator and is hell for your ears. The best solution is to put the cables in the bottom of the case and the power in a 5.25-inch bays, if you have one free!

Placing the fans

Well, it's not hard! We must place the extraction fans in the back of the case, the extraction fans on the edge of the box, fans suction side and placed at the top of the enclosure or vacuum extraction, according to your desires and your needs. However pay attention to the design of the fan. Indeed, we prefer having well designed and beautiful, rather reserved for cooling radiators.

Choosing your Fan.

Choosing the System Unit

The choice of housing will be based on several criteria:
  • The size of your motherboard
  • Your requirements

Your motherboard has a size well defined and fixed. It will choose the first case based on that.
Like the cold? Want to overclock? You will need at least 3 fans for having a box worthy of the name.
Like the silence? Choose soundproofing to the number of fans and look noise due to (x) fan (s) in extraction (<17dBa for silence).

Specific cases

Some cases are still at hand as laptops where space for air circulation is very limited.

Laptop Computers

The laptop sees its components compressed in a tiny box and plastic. Installed on your clothes, your bed, it will quickly heat up.

There are methods to cool laptops, but I find unsavory. The fans do nothing and the system is more efficient in most cases the elevation of the computer. Once a little high, air will be evacuated without obstacles and the evacuation will be faster.

We remember all laptops exploding causing injury. Those days are behind us, but who knows, keep your laptop cool and your knees intact.

The essential details

As elsewhere, the details are often important. I speak here of the thermal paste and many other things ;-)

The thermal paste

The thermal paste, which is located within the heart (GPU, CPU) is used to establish contact between the radiator and the surface of the heart so as not to leave empty, because the air is very bad driver. We must apply the right dose. It should then (with a rigid card for example) spread the paste over the surface of the heart so that the contact is total.

The thermal paste has a very long life (usually more than 2 years), there is no need to change every month!

As for thermal pads, adhesive that supposedly act as small conductors of heat, I advise you to switch to the dough as soon as you can, you will get several degrees.


Yes, the air drawn in by your computer is full of dust and it will be quick to get stuck in the radiators or fan blades. Cleaning every month is a good idea if you often have your PC switched on. The cleaning will be a bomb with dry air and a slightly damp cloth or your breath and a rag. Attention to the ideas of vacuum cleaning, a screw is lost very quickly!

The different materials of the radiator

As you know, all metals are more or less drivers! Here is a list of conductors:
  • Silver (429 W / (m.K))
  • Copper (401 W / (m.K))
  • Gold (317 W / (m.K))
  • Aluminum (237 W / (m.K))
  • Zinc (116 W / (m.K))
  • Nickel (90.7 W / (m.K))

You can get an idea of the mediocrity of aluminum. Of course, we must take these results with tweezers, the purity of the metal in question playing heavily on the conductivity.

Note that

If you have overclocked components of your PC and that you are trying to find a way to cool down your PC to avoid damaging the hardware, here are some cool ideas
  • DICE/Liquid Nitrogen/Liquid Helium Cooling : an effective method with temperatures around from -90 to -220 °C (but reserved to very experienced people with overclocked components, and this method can not be used for everyday's use, but only for benches...).
  • Install a Water Cooling Kit: "Water inside your PC, it's not a joke. If you are using high end components, even the fastest and most efficient fans will not be able to cool down PC. In these cases, installing a water cooling kit can help. The Water Cooling Kit is good alternative, the water enclosed inside the transfer system cycles down to the CPU, through a pump, where it can absorb the heat and then it pumps the hot water out of your computer where the heat can dissipate.
  • Install a Phase Change Unit: these are the most efficient of cooling technologies. Its very expensive and difficult to install, it also consumes a lot of power : its like having a fridge in your PC, but beware it will cool down your CPU,but may also freeze it if not well calibrated.
    • Well, it's over, I hope I have managed to guide you in your choice!

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