Why do you need thermal paste for a processor and is it possible to do without it? Thermal paste - what is it and what is it for? What does thermal paste do on the processor?

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What could be simpler than applying thermal paste? I plopped a drop into the center of the processor cover, plopped the cooler on top, twisted it, snapped the fasteners, and it was done. It will press itself - it will spread on its own. But there is no need to change it, this is not the king’s business! Is this approach justified?

Why do you need thermal paste? After all, we lived without her before

Yes, the first Intel 8088 processors simply did not need cooling. The need for small heatsinks, glued with hot melt adhesive or secured with pressure plates, arose in the era of the late 486 processors. Intel Pentium and AMD K6-2 already required a heatsink with a small fan. But even then no one thought about the need to use thermal paste. The processors were ceramic and emitted no more than 10 W of heat.

The active use of thermal pastes found its application after the release of Intel Pentium III and AMD Athlon. The small silicon chips of these CPUs generated 30 to 70 W of heat. Further more.

The hottest modern central processors can generate up to 250 W of heat, and video cards - even more. For comparison, a burner on an electric stove produces approximately 1000 watts.

A modern gaming PC, as a rule, requires a power supply with a power of 500 W or more, and if you use a dual-processor workstation and several video cards in SLI or CrossFireX mode, then a kilowatt power supply is not always enough.

In other words, you have at least 1/2 of the electric stove burner in your housing. In winter the room can be heated. Naturally, such an amount of heat must be somehow removed from the system unit, for this we need thermal paste.

How will thermal paste help?

To understand, you will, alas, have to dive a little into the school physics course.

All metals and their oxides, along with electrical conductivity, also have thermal conductivity. Dielectrics do not conduct electricity, but conduct heat. Any dielectric has a certain safety margin, after which an electric discharge passes through it. Air is a dielectric. Like any gas, it conducts heat poorly.

So, the silicon crystal of the central or graphics processor heats up and generates heat during active calculations. The heat from the crystal is absorbed by the metal cover of the processor or, less commonly, directly by the heat sink of the cooling system. Next, the heat is transferred to the radiator, which is dissipated into the environment. To increase the efficiency of heat dissipation, fans are usually used to blow cool air through the radiator.

Provided that the surface of the crystal and the heat sink are perfectly flat, thermal paste would be useless. But have you ever seen anything ideal in this world? Even a mirror, if you look at it through a household microscope, turns out to be far from being as smooth as it seems at first glance. And there are also convexities or concavities with a formally mirror surface.

That is, in practice, when we install a cooling system on a processor or GPU, there are spaces filled with air between these two surfaces. And the less smooth the surface of the chip cover (crystal) and the heat sink, the larger the air cushion between them.

It is in order to eliminate the air cushion between the processor and the cooler that thermal paste is needed. As a rule, it does not conduct electricity, but there are thermal pastes that are electrically conductive (“liquid metal”) or thermal pastes with the addition of metal particles.

Any thermal paste dries out over time as the liquid that binds the particles that make it up evaporates. In this case, microcracks appear in the layer of thermal paste, into which air penetrates and reduces its effectiveness. For this reason, thermal paste has to be changed from time to time. Alas, nothing lasts forever in this world.

How to apply thermal paste correctly?

Recently, there are often videos on YouTube where “experts” of different levels of preparedness test 5–10 thermal pastes, comparing them with each other and drawing far-reaching conclusions. Moreover, they spread thermal paste, as a rule, like butter on a sandwich, or “professionally” put a fat drop in the center. Let's leave the value of the results of such tests to the conscience of video bloggers. However, even after watching a dozen of these videos, the question of correctly applying thermal paste remains open. Let's figure out how to apply thermal paste correctly.

1. Before applying new thermal paste, you must completely remove the remains of the old one. You wouldn't put shoe polish on mud-covered shoes, would you?

2. Thermal paste is applied as thin a layer as possible. Often the kit includes a special spatula for application - do not neglect it.

A thick layer of thermal paste dramatically reduces cooling efficiency because the thermal paste's thermal conductivity is worse than that of the heat sink and processor cover.

3. If you are applying thermal paste directly to a processor die that has SMD components soldered around it, it is not recommended to use electrically conductive thermal paste. If you decide to do this, in order to avoid chip failure, thermal paste must be applied so that it does not get on the SMD components.

Is there anything else that needs to be done after application?

4. Before finally installing the cooling system, it is advisable to ensure that

The contact between the heat sink and the processor ensures sufficient heat transfer. To do this, you need to attach the cooler to the processor, press it, and then remove it. There will be traces of thermal paste on the cooler and processor; they should match and be as thin as possible. If the layer of thermal paste is thicker on one side and thinner on the other, then one of the surfaces is uneven. You may be installing the cooler incorrectly. In the worst case, you will have to level the heat sink or buy another cooling system.

5. The pressure of the cooling system to the processor should be equal on all sides. When the heat sink is skewed, the cooling efficiency decreases for the reason described above.

How often should it be changed?

6. Any thermal paste must be changed at least once a year, and preferably once every six months. Liquid metal remains effective for up to 5 years. Depends on operating conditions.

7. The thicker the thermal paste, the more difficult it is to apply and the lower its effectiveness. Don’t expect that the tube of KPT-8 bought 20 years ago by your grandfather will last you another 20 years.

Will toothpaste work?

No. You should not use improvised means instead of thermal paste - toothpaste, ketchup, mayonnaise, acne ointment, hand cream, etc. Firstly, it is not known how aggressive the composition of the substance that you apply instead of thermal paste is. Secondly, they usually use water as a liquid, which will evaporate in a couple of days, and in the process of evaporation can cause a short circuit. Thirdly, organic substances tend to turn sour (rotten) with all the ensuing consequences.

So, there is nothing complicated about applying thermal paste. The only question left is to choose it from all the variety on sale. Is it worth overpaying for a “brand” or will the cheapest thermal paste do? How big is the difference between different thermal pastes of the same brand? Are electrically conductive thermal pastes really more effective than dielectric ones? What is a “thermal pad” and why is it needed? But more on that next time.

Before applying thermal paste to the processor, you should figure out how often this is done and why. The next step is the correct choice of insulating material. And finally, the last thing is the application process itself, which is relatively simple, but still requires compliance with certain rules that are not always known to non-specialists.

The need to change thermal paste

The processor is one of the most important parts of a computer. With its help, millions and even billions of operations are performed per second, resulting in overheating. The use of fans with radiators helps to avoid a critical situation when the processor temperature leads to malfunctions. Excess heat is transferred to the cooler, closer contact with which is ensured by a special insulator - thermal paste. The same goes for a video card that overheats during prolonged use (except for options with passive cooling, when the radiator is already attached to the GPU).

If the paste is not used, something like the following may happen:

An overheated processor will cause the system to freeze, reducing usability and even leading to the risk of losing information;
The motherboard will completely fail, leading to the need for serious computer repairs.

The first time the paste is applied immediately after installing the processor on the board, if the assembly is done independently. For a PC that has already been assembled and is under warranty, and especially a laptop, this should not be done because of the possibility of losing the right to free service.

In the future, thermal paste is changed on average once a year for powerful and, especially, overclocked processors, both central and graphic. For lower-performing chips, the material can be applied less frequently. The reason for early replacement is slowdown of the device, unexplained reboots and freezes.

When choosing an insulator suitable for lubricating a processor, you should not pay attention to cheap options like KTP-8. Moreover, the thermal paste market has more effective materials created over the past few years.

Most of the materials are made using silicone and zinc oxide. Although the packaging of some types of pastes contains information about the presence of silver, ceramic or carbon particles in the composition. They increase the contact area between the processor and the heatsink, increasing system reliability.

Note! For the most powerful processors, it is worth using materials containing copper and gold. These metals have the highest thermal conductivity among all that paste is made from.

Application stages

Even knowing how to apply the paste correctly and having the right material, you can make a mistake that will lead to disruption of the processor. Therefore, during the work process, certain rules should be observed:

The paste is applied evenly and distributed over the entire area of the lubricated processor and that part of the radiator that comes into contact with it;
The thickness of the layer should be minimal - almost transparent, allowing you to see the symbols written on the part;
There cannot be gaps or breaks in the thermal paste, leading to a decrease in contact.

Step 1. Preparatory work

Before starting work on lubricating the processor, you need to disconnect it from the network and remove all parts that prevent you from getting to the chipset itself. Including the wall of the system unit, the radiator and its cooler. For a laptop, you must additionally remove the battery.

Step 2. Cleaning up old residues

After removing the cooling system, remove the remains of dried material left over from the last time. They also do this with a new processor that has already had thermal paste applied - usually the cheapest and most ineffective options are used when selling.

Important! To remove paste from the chipset and radiator, you must use cotton swabs or cotton napkins.

The easiest way to remove grease is to use isopropyl alcohol or an alcohol solution (70–90%) in which the materials used for wiping are wetted. For insulator that has not completely dried, you can also use a ruler, and for hardened insulator, you can use a regular school eraser. The latter method takes a relatively long time, which is required to rub the metal part until it shines, but as a result the processor remains intact.

The need for careful removal is caused by uneven surfaces of the processor and radiator, as a result of which microscopic particles may remain on them, negatively affecting thermal conductivity.

Step 3. Application and distribution of material

The first stage of application is to place a small drop of paste in the central part of the surface of the part to be lubricated - that is, the processor. The cooler radiator does not require lubrication at all, since it has an area larger than the total contact surface. And by applying an insulator to it, you can waste extra material and even short-circuit the contacts on the motherboard.

Distribute the paste over the processor using:

A plastic card or other small object of the same thickness (for example, a SIM card);
A special brush (spatula), sometimes sold together with thermal paste or purchased separately;
Wear rubber gloves on fingers.

If material accidentally leaves the processor, it should be carefully removed using a special solution.

For each type of paste, the answer to the question of what layer to apply it with is different. For ordinary material this is approximately 0.5 mm. For paste containing precious metals, about 1 mm. Sometimes one drop squeezed out of the tube may not be enough to lubricate. In this case, apply a second one and repeat the same steps.

Step 4: Shut down

Once the paste is applied, the job is finished. Now you need to install the cooler on the chipset before snapping the special fasteners into place and return the entire structure to the motherboard. After this, the fan is connected to power, and the computer or laptop is put back together.

After turning on the PC, you should check in the BIOS how many degrees the system shows. On average, the processor should heat up to no more than 40 degrees. For AMD or Semptron models, temperatures up to 60–90 degrees are allowed.

Overheating of the computer, causing the system to freeze, interferes with work or gameplay (given that both the CPU and GPU are under high load during gaming). And in order to avoid such a situation, you should, first of all, apply thermal paste on time. Secondly, carry out preventive maintenance by ensuring proper care of the insides of the device - removing dust from time to time and cleaning the ventilation holes. And for PC users who are doing this kind of work for the first time, it’s worth checking out the video clip showing how to apply the paste correctly.

Thermal conductive paste, or thermal paste, is a very plastic substance with a large thermal conductivity coefficient, necessary to improve the heat exchange of the radiator and (or other electronic elements that intensively generate heat). Thermal paste is a homogeneous mass. Very often white or gray, much less often silver or blue.

A few years ago, processors did without thermal paste, but now it is an integral attribute of any powerful or medium-power processor. Because now it is possible to overclock the processor by 10-15%. This feature is provided by the manufacturer and is very easily done in software by changing the settings in the BIOS. The use of thermal paste is explained by the fact that an air gap appears between the processor and the radiator due to the unevenness of their surfaces. Consequently, heat dissipation deteriorates by 15-20%. Nowadays, very powerful processors are produced that operate at the limit and generate intense heat. To increase heat dissipation, you cannot do without thermal paste.

Necessary requirements for thermal paste:

maintaining consistency when heated (using non-drying materials);
high thermal conductivity;
non-flammability;
corrosion resistance;
dielectric properties;
hydrophobicity;
oxidation resistance;
no harm to health.

There is a type of thermal paste called hot glue. This is thermal paste that has adhesive properties. It is used to attach electronic components to each other when there is no mechanical fastening of the elements, or this type of fastening is not provided/difficult.

How to use thermal paste and hot glue.

We clean the surfaces of the components from dirt and dust and apply a thin layer of paste. Exactly subtle. Make sure that the elements are installed correctly, remove excess thermal paste using a neutral solvent or mechanically.

The main mistake inexperienced PC assemblers make is applying a thick layer of paste. The layer should be minimally thin and uniform. Some believe that the thicker the layer, the better the heat dissipation. But this is not so, quite the opposite. Thermal paste itself does not have great thermal conductivity. It just needs to displace all the air from the uneven surfaces of electronic components, for example, between the processor and the radiator. If the layer of thermal paste is very large, then the heat dissipation will deteriorate by 20%. The heat transfer of an element with such a layer is no different from a component without thermal paste. Heating will increase by 20 - 25°, compared to the same element, but with a thin layer of paste.

When choosing a thermally conductive paste, it is necessary to take into account its main characteristic - thermal conductivity. For domestic pastes it ranges from 0.7 – 1 W/ (m K). For example, KPT-8. There are also more advanced thermal pastes. Their thermal conductivity can be 1.5 or more. When choosing, you also need to pay attention to the range of operating temperatures, i.e. temperatures at which thermal paste retains its properties - constant consistency, thermal conductivity and dielectric constant. A very important characteristic of thermal paste is the manufacturer. Foreign pastes from Gigabyte, Fanner, and Zalman are very rare. In Russia, the most popular thermal paste is KPT-8, because it is the cheapest and most accessible. Thermal pastes NS-125 and Alsil-3 have also proven themselves well.

Notes 1. Thermal conduction is the transfer of heat, or energy, from more heated elements to less heated ones as a result of the interaction of molecules and their movement. 2. When speaking of thermal conductivity, we mean the coefficient of thermal conductivity.

Video about what thermal paste is needed for and how to use it correctly.

Hello dear readers.

Today I would like to tell you about a small but very important component, what it is and why thermal paste for a processor is needed. This may be the first time you've heard this concept. As we all know, the processor of our computer or laptop tends to heat up.

In order to prevent it from overheating, there is a processor cooling system: heat is transferred to the radiator, and the fan blows cold air over the radiator itself - this is called a cooler. So, there is also such a thing as a thermal interface.

A thermal interface is a kind of gasket between a heating element (for example, a processor cover) and an element that removes heat (cooler). Thermal interfaces come in the form of compounds, copper plates, thermal rubber solder, and of course thermal paste (heat-conducting paste).

Why is thermal paste used? Thermal paste differs from all thermal interfaces in that it has a viscous consistency.

No matter how well the radiator heels are polished, there will still be microscopic holes on them. There will be air in these holes. And besides, the surface of the processor cover also has micro holes. Usually no one polishes the lid. :)

The air tends to heat up and, accordingly, heat transfer will decrease, so you need to remove it from there. This is why they came up with such a wonderful thing as thermal paste.

In total, it has two functions:

Naturally, it is used for better contact and, as a result, cooling, etc. But remember the main function!

Thermal paste is needed primarily to fill holes (microcracks) in the surface so that there is no air there.

Since it is precisely because of the air that the necessary cooling does not occur (the air must be removed from the heating element.) And so that it does not settle in these cracks, this paste is used.

In addition to removing air, it itself is a heat conductor. In the characteristics of pastes they write such a parameter as W/mK - Watt per meter per Kelvin. The higher this indicator, the better the thermal conductivity, and accordingly, the better the quality of the paste.

The paste is also used for video cards, that is, it is applied to the video chip. The principle is similar to the processor - it serves to ensure better heat transfer and prevent overheating of the video card.

Thermal paste must be applied in an even, thin layer. You should delve into the definition itself, the particle “paste” means that the consistency should be viscous; it must not be allowed to dry out, otherwise it will lose its original purpose. It must be replaced every 6-10 months (both on a PC and on a laptop) to maintain good heat transfer.

Someday I’ll write a separate post about applying the paste.

That's all for today, I hope my article was useful to you. Oh yes, I forgot something else. Here on the Internet there is information that supposedly you can replace thermal paste with toothpaste :)). Do not under any circumstances believe this nonsense! Toothpaste was developed for other purposes, and if you use it on a computer, it will instantly boil and dry. Ripping it off is not a rewarding task.

Now everything seems to be done.

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Owners of personal computers and laptops who are faced with the problem of low operating speed and spontaneous shutdown of the device have often heard that everything can be solved by replacing thermal paste. Often included as an additional service. Such pleasure is quite expensive. It's time to find out what thermal paste for a processor is, why it is needed, how to replace it yourself, and which manufacturer to give your preference when purchasing.

Delving into physics

From the school physics course, you can recall information about thermal conductivity. There are materials that are not those that partially conduct, and those that completely transmit temperature. For example, insulating tape has minimal thermal conductivity, so it is used to wrap exposed wire sections to prevent fire. Computer paste, on the contrary, plays the role of a heat conductor, due to the homogeneity of the mass and high thermal conductivity, and is able to transfer the heat generated from the processor to the cooling system. This is why thermal paste is needed for the processor.

There is no tight contact between the processor and the radiator of the cooling system. There are many microscopic gaps into which air enters during installation. As you know, air is a poor conductor. Therefore, a good one was developed which, during installation, not only displaces air, but also provides the device with excellent heat transfer.

Thermal paste needs

Having understood what thermal paste for a processor is, why it is needed, and having studied the principle of its operation, you need to find out where it can be used. First of all, when installing a cooling system on a processor in a computer. Thermal paste must also be applied to the video card, in the places where the chips come into contact with the radiator of the cooling system. If your computer's motherboard has additional cooling radiators that are removable, you should definitely use thermal paste. The problem of overheating also exists in laptops. Basically, mobile devices have a single cooling system for all components that generate heat.

A little about thermoplastic glue

It turns out that if the computer gets hot, thermal paste for the processor will help it. It will be possible to find out which is the best of all those offered a little later, and before purchasing it is important for the user to know that, in addition to thermal paste, there is also hot-melt adhesive on the market. Unlike thermal paste, it can change its physical state under the influence of heat and transform at a certain temperature from a solid state to a liquid form. In computer technology, hot melt adhesive is periodically used, especially in laptops. When heated strongly, the mixture melts and displaces air, providing high thermal conductivity, which is maintained in the future.

In fact, if the processor reaches the thermoplastic glue, it will burn faster, because 100 degrees Celsius is a lot for crystals. And at operating temperatures of 70-80 degrees, solid hot melt adhesive shows low thermal conductivity in relation to thermal paste. In addition, before replacing the thermal paste for the processor with thermoplastic glue, you need to be aware that several years later, when it becomes necessary to replace the thermally conductive component, it may be difficult to clean the heatsink and processor from the glue.

Doing simple work with your own hands

Replacing thermal paste on a processor will not be difficult for an ordinary user who is far from IT technology. To do this, you need a little desire and, of course, thermal paste for the processor. Everyone knows how to apply butter to bread - the layer should be minimally thin, but cover the entire surface 100%. Naturally, before applying thermal paste to the processor, you need to clean it with a rag to remove any remaining old paste. The radiator is also cleaned to its factory shine. After applying a thin layer of thermal paste to the processor, you should lean the heatsink on top and fix it. If the surfaces become separated during fixation, the procedure must be repeated again, from the very beginning.

It is important to remember that the processor does not need to be removed from the motherboard. By removing the processor from the slot, you can accidentally bend one of the legs on it or on the motherboard, then it will easily break during installation.

How to dismantle a radiator

Before replacing the thermal paste for the processor, you need to remove the cooler. There are three main types of fastening.

Plastic screws with latch. There are arrows on the top of the four screws; after turning the screws in the desired direction until they stop, you need to pull them up a couple of centimeters. The latches will engage and the radiator can be removed. When reinstalling, you need to return the screws to their original position, and also make sure that the latches on the other end of the screw are installed smoothly and are not bent, otherwise you will not be able to insert them into the narrow connectors on the motherboard without a sharp object. If installation is unsuccessful, the thermal paste for the processor is always displaced. We figured out how to reapply it.
There are metal screws that can be unscrewed with a regular screwdriver from four fasteners, and the cooler can be removed without any problems. Installation is as easy as removal.
The screwless latch was widely used on older processors and is now falling out of use. By lightly pressing your fingers on the special latch handles, the mechanism opens, releasing the radiator from the “captivity” of the latch. Installation is done in reverse.

Video adapter cooling system

A good thermal paste for the processor is also used in the cooling system of video cards. After all, if you look at the statistics, video adapters burn out more often due to overheating than processors. For some reason, when servicing a computer, service centers often change the paste only on the processor.

Removing the cooling system on a video card is very simple, since it is almost identical for all manufacturers. In gaming models, the heatsink is screwed to the case with spring-loaded screws, while cheap models are installed with metal latches. After removing the radiator, it doesn’t hurt to go out into the open air and blow it out of dust and debris. Unlike a heatsink on a processor, an expensive video adapter with a turbine gets very clogged with dust. As in the case of the processor, you need to carefully clean everything with a napkin or rag, apply a thin layer of thermal paste and carefully assemble the structure.

About fans of overclocking processors and video adapters

Those who want to increase the performance of their computer to run the next game have to resort to the so-called overclocking of the processor and video adapter. During overclocking, the voltage in the chip increases, and, accordingly, the temperature. Many users on social networks are discussing which thermal paste to choose for a processor or video adapter that will work 20% faster than normal. Trying to overcome the problem of heat generation by using thermal paste is considered stupid. First of all, you need to look towards changing the cooling system.

At a minimum, if you have low finances, it is worth installing a high-quality cooler with a copper core, copper tubes and a fan that can drive a strong air flow. If finances are not limited, you can install water cooling, which will solve all overheating issues. Finally, no one prohibits the use of a cooling system. But there can be no discussion of thermal paste for overclocking systems. The difference in thermal conductivity is a couple of degrees Celsius, but not tens.

What is the difference between products from different manufacturers?

Choosing thermal paste for a processor should not be complicated by the abundance of various offers on the market. The differences between thermal pastes from different manufacturers are small, but the effectiveness is almost identical. Even though manufacturers claim that only their product transfers all the heat from the processor to the radiator 100%, however, judging by numerous reviews and tests, there is not much difference between manufacturers. The only difference is the price of thermal paste for the processor. It’s hard to say which one is better; it’s easier to describe the characteristics, advantages and disadvantages of most thermal pastes on the market, and let the buyer decide for himself which brand to give preference to.

Domestic manufacturer

It is unlikely that sellers in computer stores in the post-Soviet space will quickly name the markings of foreign-made thermal paste, but everyone, without exception, is familiar with the Russian products “KPT-8” and “Alsil-3”. The first option is produced in tubes and jars, and the second is sold in a syringe. Even though there are different meanings and composition written on the container, judging by the substance, smell, color and test, it is very similar that this is the same thermal paste for the processor. It’s hard to say which one is better, but judging by user reviews, “KPT-8” in a tube at a low price contains more paste, which means it lasts for a long time.

Market of foreign thermal pastes

All foreign-made thermal pastes, such as Zalman, Thermaltake, Titan, Gigabyte and Fanner, differ from each other only in color. The tubes are identical - in the form of a disposable syringe with a screw cap instead of a needle. The dye added to the thermal paste has a bright color; it is very difficult to erase from surfaces and wash off hands. We can say that this is the most easily soiled thermal paste for a processor in the world. It’s difficult to say for sure which of them is better, because each of the listed companies has been on the market for several decades and definitely knows a lot about cooling systems.