Cooling of various components is one of the favorite topics of overclockers (though not only them). Good ventilation of the case is of great importance here - after all, by lowering the temperature in it by at least a couple of degrees, we will also lower the temperature of all the elements inside. Unfortunately, I haven’t come across a more or less accurate method for calculating the ventilation of the case. But in abundance from article to article there are general recommendations that have become bronzed from frequent use and are no longer critically perceived.
The most common of these myths are:
- The fan blowing capacity should roughly correspond to the blowing blower capacity
- It is imperative to let in cold air from below, and let it out from above
- The more expansion slots and 5-inch bays are filled in the chassis, the worse its ventilation
- Replacing ordinary loops with round ones noticeably improves the ventilation of the case.
- The front fan significantly reduces the temperature inside the case.
As a result, the struggle for ventilation of the case often comes down to installing fans of the maximum possible size and performance in all regular places, after which a drill is taken into the hands (hacksaw, jigsaw, chisel, sledgehammer, "grinder", autogenous - underline the necessary :-), and fans stuck in abnormal places. After that, to heighten the effect, a couple of fans are added to the inside of the case - usually to blow off the video card and hard drive.
It is better not to talk about the time, effort and money spent on all this. True, the result is usually not bad, but the noise emitted by this "battery" at full speed goes beyond all conceivable limits, and it sucks dust at the speed of a vacuum cleaner. As a result, the body soon begins to grow overgrown with fenbasses and reobases, becoming like a mid-range mixing console. And the process of launching the game, instead of just clicking the mouse, now resembles preparing for an airliner to take off - we must not forget to add speed to all these fans. In this article I will try to show you how you can achieve a similar effect with "little blood".
Diagonal running
All mass cases can be divided into three types - desktop, tower with top (horizontal) power supply unit and tower with side (vertical) power supply unit. The main market share is occupied by the latter two. Each has its own advantages and disadvantages, but the third type is considered the worst in terms of ventilation - here the processor ends up in a windproof "pocket" next to the power supply unit, and it is quite difficult to organize the supply of fresh air there.
The general principles of ventilation are simple enough. First, fans should not interfere with natural convection (from bottom to top), but help it. Secondly, it is undesirable to have windproof stagnant zones, especially in places where natural convection is difficult (first of all, these are the lower surfaces of horizontal elements). Thirdly, the greater the volume of air pumped through the hull, the smaller the temperature difference in it compared to the "outboard" one. Fourthly, the flow does not really like various "tricks" - changes in direction, contraction-expansion, etc.
How does air exchange take place? Let's say a fan is pumping air into the case, while the pressure in it increases. The relationship between flow and pressure is called fan performance. The higher the pressure, the less air the fan will pump in and the more it will come out through the vents. At some point, the amount of injected air will be equal to the amount of outgoing air, and the pressure will not increase further. The larger the area of \u200b\u200bthe ventilation openings, the lower the pressure this will happen and the better the ventilation will be. Therefore, simply increasing the area of \u200b\u200bthese holes "without noise and dust" can sometimes achieve more than installing additional fans. And what will change if the fan does not blow in, but blows air out of the case? Only the direction of flows will change, the flow rate will remain the same.
"Classic" options for organizing ventilation of a case with an upper power supply unit are shown in Fig. 1-3. Actually, these are actually three varieties of the same method, when the air flows diagonally of the body (from the front lower corner to the rear upper corner). Windproof zones are shown in red. The resistance to the flow does not depend on how densely they are filled - it still passes by them. Pay attention to the lower area in which the video card is located - one of the most critical computer components to overheating. Installing the front fan allows you to supply a little fresh air to it (and at the same time to the south bridge), knocking down the temperature by a couple of degrees. True, in this case the hard drive is "on the sidelines of life" (if it is installed in its regular place). Figure 4 shows why this happens. Here the air flows through the fan are schematically represented (the darker color corresponds to the higher speed). On the suction side, air enters evenly from all sides, while its speed decreases rapidly with distance from the fan. On the discharge side, the "range" of the air flow is noticeably greater, but only along the axis - a windproof zone is formed on the side of it. The same "aerodynamic shadow" is obtained behind the fan hub, but it quickly fades away.
To illustrate, I will give an example from life. Looking for the best way to cool my desktop, I turned the fan in the PSU upside down. In theory, this should improve the cooling of the power supply unit - after all, now it is blown with fresh air, and not used from the case. However, the BP thermal sensor showed the exact opposite - the temperature increased by 2 degrees! How could this happen? The answer is simple - the board with the sensor is installed away from the fan and therefore found itself in the aerodynamic shadow. Since, along with the thermal sensor, some other elements were in this shadow, in order to avoid their failure, the status quo was restored.
The criterion of truth
Now let's move on from theory to practice. Our main task is to increase the area of \u200b\u200bventilation openings, and preferably quickly and without the use of locksmith tools. Their area should be at least equal to the effective area of \u200b\u200bthe fan (that is, the area swept by the blades), and it is better to exceed it one and a half times. For example, for an 80 mm fan, the effective area is approximately 33 cm2. If there are several fans and they all work for blowing (or, conversely, all for blowing), their effective area is added up. This measure is especially relevant for cases of old designs, which still remember Pentium-2 and nevertheless continue to be produced (and sold) until the dies are completely worn out.
My desktop Codegen, which has already survived three motherboards, belongs to such "veterans". Of the "convenience" it has a place for a 90-mm front fan, which, according to the designers, should suck in air through a slot at the bottom of the front panel with an area of \u200b\u200bonly 5 square meters. see, and symbolic holes with a diameter of 1.5 mm opposite it (later I drilled them in a checkerboard pattern up to 4 mm - it became even more beautiful). Of course, the hull is not a submarine, the air will be sucked in through other small cracks and leaks, which cannot be accurately recorded. But all the same, ventilation in normal mode resembles running in a gas mask.
Computer configuration during testing:
- CPU Athlon T-red-B 1.6v. [email protected]X11, cooler Evercool ND15-715 is connected via 3-pos. switch (second speed used, 2700 rpm)
- M / b Epox 8RDA3, bridge airflow off
- video Asus 8440 Deluxe (GF4ti4400), act. the cooler covers the chip and memory.
- 512 Mb RAM Hynix
- HDD Samsung 7200 rpm
- CD-ROM, FDD, Rack container
- Modem
- TV / capture card Flyvideo
- PSU Codegen 250w
- Total power (without power supply unit) - about 180 W
The processor temperature was measured through Sandra, video cards - using built-in sensors through SmartDoctor, in the case under the top cover above the processor (don't forget - the desktop case) an external sensor of an electronic thermometer was placed, the second sensor of this thermometer measured the temperature in the room. Then the results were brought to an external temperature of 23 degrees.
The system was loaded by running the 3DMark2001SE game test cycle. In the initial state, the temperature in the case exceeded the external temperature by 15 degrees, the temperature of the video card (chip / memory) was 55/38 degrees higher, the processor temperature by 39 degrees. For comparison, measurements were taken with the lid open. Results: the temperature of the video card is 44/30 degrees higher than the external one, the processor temperature is 26 degrees higher.
First, let's try to follow the traditional path. What is the first thought that comes to mind when looking at this case? "Since there is a hole for the fan, there must be at least something there" (quite like the Golden Calf). Well, let's put it on. What's the result? The temperature sensor in the case did not react at all to our manipulations, the temperature of the processor dropped by 1 degree, and the temperature of the video cards by 4-5 degrees (by the way, another traditional step gave about the same result - installing a Gembird SB-A blover next to the video card). Actually, this is where the "traditional path" ends.
Now we will return everything to its original state and go the other way - we will pull out the two plugs for the expansion slots next to the video card. This kills two birds with one stone: a new "hole" appears for ventilation of the case and the stagnant zone of the video card is eliminated. In addition, we will break off the protective "comb" at the front air intake (fortunately, it is from below and it is still not visible) - its area will triple, and the total size of the ventilation holes will be 45 square meters. cm.
The result was not long in coming - the temperature in the case dropped by two degrees, and the video card made us even more happy, dropping at once 9 degrees on the chip and 7 degrees on the memory. Agree, a good result, besides it is completely free. This option can be recommended for cards with a passive cooler as an alternative to installing a fan. And if this is not enough? Adding a front blower fan leads to a paradoxical result - the temperature of both the case and the video card ... rises! A little, just one degree, but nevertheless ... The explanation is simple - now more air enters the case through the front opening and less - through the rear one past the video card.
And if you put it on blowing? This is a completely different matter. Both fans (in the power supply unit and the additional one) are now turned on in parallel, their costs add up, and here's the result - the video card "got colder" by another 3-4 degrees, and the total temperature decrease compared to the original version was 12 degrees for the video chip, 10 degrees for video memory and 5 degrees in the case (and, accordingly, in the processor). Note that the graphics card is colder here than in an open case! The expenses were limited to the purchase of one medium-power case fan.
Finally, the last option, "extreme" - all three fans (power supply unit, front and blower) are blown out, in addition we open one more slot at the back. The Blover was installed in the bottom (of the two) five-inch bay instead of the removed Rack container. Results - the processor "got colder" in comparison with the previous version by 4 degrees (and now it is the same 4 degrees hotter than itself in an open case), and the video card dropped a couple more degrees. True, the temperature sensor in the case did not show any decrease - cold air passes below it, since additional fans take air not from above, but from the middle of the case. The general results are summarized in the table. It shows the absolute temperature of the components, referred to 23 degrees in the room.
From bottom to top, obliquely
Now that we have understood and tested in practice the general principles of effective ventilation, we will apply them to the most common case - a tower with an upper power supply unit.
Figure 6 shows the most efficient way to cool such a case. An additional fan on the back panel actually provides the same blowdown mode as in my last experiment. Since almost half of the heat is generated by the processor, it makes sense to supply some of the cold air directly to the zone of its operation. This is done through a free three-inch or five-inch compartment on the front wall - both of its plugs (plastic and metal) are removed, and how to decorate the resulting hole is a matter of skill and imagination. In the simplest case, you can buy a socket with a couple of small fans (which can be removed immediately, there is no sense in them), since there are many varieties of such "bells and whistles" for five-inch compartments - from a regular grille to panels with a built-in electronic indicator, USB ports or fenbass their lattice area is smaller).
The installation of the Rack container also provides a good purge. Please note that all this economy must be placed in the lowest compartment. The choice of a specific option depends on what first needs to be "frozen". If the processor or memory overheats, the holes need to be made larger, and if the video card, you can do without them altogether, but open more slots at the bottom. In this case, the total area of \u200b\u200bthe holes should be at least 70-80 sq. see depending on fan size. For reference: the area of \u200b\u200bone slot hole is 13 square meters. see, open three-inch compartment - 30 sq. see, five-inch - 15-30 sq. see with the above-described decorative lattice and 60 sq. cm for fully open. Another 10-15 sq. see can remove the plugs from the port holes on the rear wall. Oh yes, I almost forgot, there is also a regular air intake at the bottom of the front panel with an area of \u200b\u200b5-30 sq. see, and in some cases there are also holes in the side walls.
If the top panel has a standard fan hole, it's a sin not to use it. Put something in there that is not too powerful for blowing. If there is no such hole, you should not cut it. Instead, buy a special blover and install it in the topmost 5-inch compartment (Figure 7). This will be especially useful for those who, for some reason, do not have a hole for an additional fan under the power supply unit, or it is used to directly cool the processor. But in this version, it is worth making an air duct that directs fresh air from the lower five- or three-inch compartment to the processor area. Without it, a significant part of this flow can immediately go into the blover without capturing enough heat along the way.
In fig. 8 shows a rather exotic design with a bottom blower blowing out. It is worse than the previous two and can be used only as a last resort, when the first thing is to cool the video card. In fact, this scheme provides two independent streams - the first (bottom, from the back to the front) cools the video card, expansion cards and the south bridge, and the second (from the front to the back) cools the upper half of the case. The advantages of such a scheme are that the total blowing capacity of the fans increases, a significant part of the hot air from the video card is immediately removed to the outside, and the overall flow resistance in the case is less.
But there are also significant drawbacks. Chief among them is that, for the sake of design, the bottom openings in the front wall through which air is blown out usually have an area much smaller than the effective area of \u200b\u200bthe front fan. In addition, the stream has to change direction twice, which it hates very much. The result is the same "running in a gas mask" - for example, if the hole in the casing is half that of the fan, the performance of the fan also drops by about half, and this is without taking into account the back pressure in the casing. But the noise, on the contrary, will be more - seeping through narrow slots, small holes, intricate "squiggles" and other design delights in the front panel, the air flow may not emit an artistic whistle. In addition, the noise of the front fan (as opposed to the rear) is not shielded by the case.
You can improve the efficiency of the front fan by introducing additional air into the cavity between the front bezel and the metal front panel of the chassis. To do this, let's go along the beaten path - pull out the plastic (this time only plastic!) Plug of the lower three-inch compartment. But we still need to supply cold air to the upper half of the case, and also from the front. These streams must be separated by a baffle under the lower five-inch compartment.
Now let's look at the flow movement in the body. In the first and second schemes, the main stream moves from bottom to top. The resistance to flow is determined by the narrowest point in its path. In this case, this is a section at the level of a video card: it itself occupies a good half of the case, and on the other side there is a hard drive with a sticking cable. Since the video card cannot be moved to another place, it remains to rearrange the hard drive. It can be lowered down or placed in one of the 5 ”bays (preferably the one that is used as an air intake). In both cases, the hard drive will be perfectly blown, which will have a beneficial effect on its health. However, the narrowest point on the flow path is actually not here, but at the entrance to the hull - there its speed is an order of magnitude higher, and aerodynamic losses are proportional to the square of the speed. Therefore, "licking" and laying the plumes gives practically nothing in terms of air exchange.
I hear, I hear malicious voices - but what about horror stories about dust, which, when all fans are installed for blowing, will supposedly be sucked in wild quantities through CD-ROM and FDD? I answer. Air follows the path of least resistance and, with good ventilation, will not go into narrow cracks when there are large windows nearby. And the standard ventilation system, let me remind you, works for blowing, and in branded cases and laptops too (and there are no fools sitting, as some colleagues like to say when other arguments end :-)
In conclusion, let's say a few words about towers with a side power supply. Despite the large number of holes located in the most unexpected places, the ventilation of these cases is disgusting. If the airflow of the video card can still be improved in the traditional way (by opening adjacent slots), then you will have to tinker with the processor. For a good blowing of his "pocket", you need to somehow remove hot air from there. The most effective way is to insert into the upper fan panel for blowing out, but this is very laborious. Therefore, we will try alternative methods. In InWin cases, there are ventilation holes of unknown purpose at the top on the back wall - warm air will not come out from there, because in the case, the vacuum from the PSU fan, and the supply of cold air to the very ceiling is ineffective. To prevent them from disappearing, put the blover there for blowing. In enclosures where this is not the case, the blover can be directed forward and connected with an air duct to an empty five-inch compartment (of course, removing both plugs from it, Fig. 9).
Another option is to install a power supply unit with a powerful fan, in which air is drawn only from the side of the "pocket". There are power supplies on sale that have a 120-mm fan on the side wall - in theory, it should be enough for good ventilation. You can also do the opposite - supply fresh air to this zone with a fan or a blower through the air duct, counting on the fact that the jet will "finish off" the windproof corners. In general, these buildings provide an immense field for experiments.
There are still a few myths about the choice of fans ... but this issue should be devoted to a separate article.
Vladimir Kuvaev aka kv1
Theoretical foundations of cooling system unit elements. Cooling components
In the previous article on processor cooling, we have already mentioned that any consumer of electric current heats up to one degree or another during operation. It is very easy to determine the approximate amount of heat released; it is enough to determine the total electrical power consumed by the system unit. The consumption of modern gaming systems, for example, is in the 500-1000 W range. It is easy to calculate that the components of such computers emit up to 1 kJ of thermal energy per second. Approximate calculations show that with a system unit weighing about 10 kg, it heats up by 1 ° C in less than five seconds. It turns out that in order to heat the entire system unit to the temperature of failure of semiconductor elements (85-90 ° C), it takes only five to seven minutes of PC operation. Taking into account the uneven heating, the failure of the system in practice will occur in less than a minute. Obviously, in order to prevent overheating of the system unit and its individual elements, it is necessary to properly organize their cooling.
In fact, the task of proper cooling in the system unit of a personal computer can be conditionally divided into two complementary stages: cooling of individual components and organization of heat removal from the case of the system unit. Let's take a look at these steps separately.
Heat removal from the system unit
The task of removing excess heat from the PC system unit is not as trivial as it might seem at first glance. First, let's remember a typical tower computer case with a top-mounted power supply.
In a typical chassis without additional cooling, the exhaust fan on the power supply creates a vacuum inside the system unit. Cold "outboard" air enters through the ventilation holes at the bottom of the front panel, passes, warming up, through the area where the RAM and processor are located, and out through the power supply unit.
The diagram clearly shows that a large-sized video card, expansion cards, as well as hard drives and 5.25 "devices are serious obstacles to the passage of air and because of this, stable zones of hot air are created, which leads to an increase in the temperature of the components located in them.
Installing additional case fans opposite the CPU and a fan on the front panel will slightly reduce the size of the "hot zones", but will not completely remove them, since the airbag itself will not go anywhere and large-sized devices will still obstruct the passage of air. Air, like flowing water, always looks for the shortest path from the entrance to the exit, and the turbulence formed when it collides with obstacles does not radically solve the problem of cooling the nooks of the system unit.
Nevertheless, solving the problem of proper airflow is quite simple. Step one - install the case fans so that a rarefied atmosphere is created in the case. The total power of the fans working for the blowing should be higher than those that provide the air flow inside. I know that many experts will immediately object: "This way my computer will turn into a vacuum cleaner ...", etc. But the answer to such "experts" is the same - vacuum around the computer more often, then it will have nothing to draw into itself. In addition, no one has canceled the need for regular cleaning of computer stuffing with a regular vacuum cleaner.
Step two - ensure the flow of air into the system unit not only through the standard ventilation holes (for the sake of a beautiful design, manufacturers often make too few of them), but also near each heat-generating object. This is done quite simply. On the rear panel, you can remove the caps under the video card and expansion cards, and on the front, you can remove the caps for the slots for installing a floppy drive and unused 5.25 "slots. The result of such manipulations with the body is shown in the following diagram.
The author of the article, by simply removing the plug under the video card, lowered its temperature by 21 ° C, which was a lot of surprise himself, as he was planning to replace the cooler on the GPU, with the total budget of the whole event about 20 cu. e.
Of course, the above scheme is not a dogma. A wide variety of computer cases, a different organization of their regular cooling, a different arrangement of ventilation holes and system unit components clearly cannot match the same pattern. This typical example simply shows the general principle of correct air flow organization. Ensure the passage of cold air past all heat-generating elements, paying special attention to the video card and hard drives, and this will significantly increase the stability and reliability of the system as a whole without additional investment in expensive cooling systems.
When planning ventilation of the enclosure, take into account one more point - always the general direction of air flows should help natural air convection. Warm air rises upward, entering the system unit from below.
Cooling motherboard elements
A motherboard is a device that only its manufacturers usually pay sufficient attention to properly cooling. An ordinary PC user, by default, assumes that the developers have provided all the necessary measures for its thermal protection. And he placed the radiators where they are needed, and look, even heat pipes are laid where they are needed. This means that there is absolutely nothing to worry about. Unfortunately, such an attitude to the cooling of motherboard elements often leads to its premature failure.
First of all, let's figure out which elements of the motherboard generate enough heat to take care of their forced cooling. There are only three "hot" elements on the motherboard:
- north bridge;
- south bridge;
- surge Protectors.
Of all the above, the least problematic is the south bridge. Since it is responsible for working with slow components, even an increase in the nominal frequencies when overclocking a computer has little effect on its heat dissipation. If, nevertheless, the test utilities show too high a temperature, in most cases it is sufficient to install a small radiator on the south bridge. Since there are no mounting holes in the boards near the south bridge, the radiator is installed on hot melt glue.
The North Bridge, in contrast to the South Bridge, is a more powerful source of heat. Almost all motherboard manufacturers install standard radiators on it. In case of insufficient heat dissipation rate, a small-sized cooler should be attached to this radiator. As a rule, for its installation in motherboards, mounting holes are provided around the bridge chip. If these holes are not there, then the fan is installed on the radiator using ordinary superglue.
We cool everything that we can
Voltage stabilizers are subject to overheating no less than the north bridge. A group of stabilizers is located, as a rule, between the processor and the connector block. In modern motherboards, regular radiators are often installed on them. Top-end motherboards even have a single cooling system for bridges and heat-pipe stabilizers. However, for proper cooling of stabilizers, good airflow is much more important than solid radiators. This should be taken into account when choosing a CPU cooler. If you have a super-powerful cooler with an air flow parallel to the motherboard, or you have a liquid cooling system that does not create air flows at all, then the stabilizers can easily overheat even with good radiators on them.
Such a cooler perfectly cools only the processor
When using such cooling systems for the central processor, it is imperative to take additional measures to cool the area where voltage stabilizers are located. If your CPU cooler directs airflow to the motherboard, then in most cases this will be enough to cool the stabilizers with heatsinks to normal temperature.
In the event that, in your opinion, the cooling system is thought out correctly, all the radiators and fans are in place, the airflow is normal, but the bridge or stabilizers still overheat, change the thermal paste. Often the cause of overheating is a poor thermal interface between the heat-generating PC components and their cooling systems.
Cooling the RAM
Serious overclockers approach the cooling of RAM modules with no less responsibility than cooling the processor. If, in most cases, proper organization of air flows in the case of the system unit and installation of the simplest radiators for complete calming are sufficient to operate in normal modes, then during overclocking, high-quality cooling is the key to success.
Radiator on the RAM bar
For more reliable cooling of the RAM, manufacturers offer a wide range of devices of various types. The most inexpensive are air cooling systems, which are a set of heatsinks that are put on each memory strip and a fan block covering the entire row of strips. Such systems have a significant drawback - rather large dimensions, due to which it is often impossible or undesirable to install them next to a large processor cooler.
The cooler perfectly cools the memory, but eats up half of the air from the processor
Liquid cooling systems for RAM are deprived of this drawback. In such systems, a contact pad is attached to special radiators through which coolant is pumped. Such liquid systems show maximum efficiency, especially since there are systems that use liquid nitrogen as a heat carrier.
Recall that such drastic measures to cool the RAM are necessary only when overclocking the system. If you are not going to increase the nominal frequencies, then heatsinks on the memory bars and the correct organization of air flows in the PC case are enough.
Cooling video cards
Modern video cards, in the vast majority of cases, are well-balanced devices in terms of cooling their elements. Native heatsinks and fans installed on graphics memory modules and on a graphics processor ensure sufficient cooling of these elements in normal modes. Nevertheless, a wide range of computer enthusiasts are making serious efforts to reduce the temperature of the elements of video cards during their overclocking, since in this case the performance of standard coolers is no longer enough. And, of course, additional measures to reduce the operating temperature of the components of graphic cards must be taken if they notice instability in their operation under severe loads or test programs show data close to critical from temperature sensors.
Hybrid graphics card cooling system
The main steps to improve the cooling efficiency of video cards differ little from those described above for other components. First of all, it is necessary to analyze the air flows in the system unit and ensure a stable flow of cold air into the radiator area of \u200b\u200bthe video card cooling system. If everything is in order with airflow, but the temperature of the chip does not decrease, then you should think about replacing the standard cooling system with a more efficient one. The range of coolers for video cards is slightly inferior to the range of processor ones - powerful radiators with two or three high-performance fans, liquid cooling systems, hybrid coolers that combine the advantages of air and liquid cooling in a wide variety of options. And, of course, for the most radical overclockers, there are cooling systems that use liquid nitrogen as a coolant (rather, a coolant).
Cooling hard drives, optical drives and other devices
Hard drives and other "slow" devices are less susceptible to overheating. However, considering that they are often installed in places with insufficient ventilation, cases of failure of the electronics of hard drives due to overheating are not so rare. Therefore, it is nevertheless necessary to properly organize the airflow of controllers even for such "slow" devices, both with the help of the correct organization of air flows inside the system unit, and with the help of special winchester coolers, forcibly blowing directly into the electronics boards. Such coolers can be mounted directly on the device, or they can be a kind of 5.25 "pocket with a forced ventilation system, inside which 3.5" hard drives are already installed.
Conclusion
Organization of effective cooling of the system unit elements is one of the important elements to ensure the stability and durability of the entire PC as a whole. One of the most important steps in this work is to ensure efficient removal of excess heat from the case. In the overwhelming majority of cases, this stage will be the only one necessary for those who are satisfied with the performance of their computer in normal mode.
For a wide range of extreme lovers seeking to squeeze the maximum possible out of the computer hardware in their hands, there is a wide range of various high-performance cooling systems for any of the system unit elements, a short overview of which we have tried to give in this article.
On the very first computers, cooling did not play a key role, since the heat transfer of the first processors was very small, and they could easily do without it. But with the advancement of technology cooling and ventilation systems have become an integral part of computer life. An increase in the clock frequency of the central and graphic processors and an increase in the number of transistors in them to astronomical values \u200b\u200bled to the fact that these components began to generate very much heat, heating up at the same time and heating the space inside the system unit. And it was no longer necessary to do without special cooling.
Also, if you are overclocking your system trying to make it a little faster, you probably noticed that it will certainly get much hotter. This article will give you some tips on how to lower your computer's temperature too high.
In the case of a modern computer, many devices are collected, and almost all of them heat up during operation. Especially intense heat is emitted by the central processor, video card, motherboard chipset, RAM, hard disk controller and electrical elements of the power supply. All this "economy" must be cooled. Otherwise, overheating of any of these components can lead to its failure.
For cooling in any case, use fanbuilt into the power supply. It usually pumps air out, while sucking it in from the outside through various holes and slots in the case of the system unit. However, in modern systems, such cooling is often no longer enough, and you have to use additional fans installed in the case.
Make sure that all fans move air in approximately the same direction. For example, if the power supply is on the top and back of the chassis, and its fan is pulling air outward, you can install a fan that pulls in air from the front and bottom of the chassis.
Which way are the fans blowing in your computer case? If you only have one fan - in the power supply - then you're in serious trouble, no matter how you answered the question. If the fan blows air out, then it does little to help cool the internal devices, especially if there are no vents in the front of the case. If, on the contrary, it sucks in air inside, then a normal air flow occurs only if there is no device directly in front of the power supply. This is unlikely, since most modern system units have 5-inch drive bays opposite the power supply. Subsequently, such a situation in which there is only one blower fan, and no blower fan, can become very dangerous for the "health" of the computer.
In general, the main purpose of the system unit is to protect electronic components from dust, dirt and pets. However, if you completely close the system unit and install only one fan pumping air inside, then you can consider yourself the proud owner of a very expensive vacuum cleaner. Dust, dirt, fine fabric fibers, hair, wool, etc. that accumulate inside the case. can conduct electricity. In modern systems, the components operate at low voltages, and if some of the current picks up dust, there is a real danger of the computer malfunctioning.
Thus, good system cooling can be achieved by using two or more fans in the chassis. As a rule, the fan in the power supply works for blowing, and the system fan located at the opposite point of the case works for blowing. However, the opposite situation is also possible, it all depends on whether the system fan can take in enough air from the outside.
Perform the following simple test. Open the system unit, turn on the computer. Take a piece of paper and bring it to each fan. This will determine the approximate direction and strength of the air currents.
During such a check, you may encounter one of the following situations:
1. The PSU fan draws air into the chassis, but the system fan sits directly opposite it and immediately blows that air out (or vice versa). In such a situation, almost certainly air will practically not move around the rest of the system unit devices.
2. Two or more fans located at opposite ends of the chassis blow air inward. So you can really reduce the internal system temperature, but this option is completely unsuitable in terms of cleanliness. There are no air filters inserted into the system fans, so any dust in the air ends up inside the case. Considering that tower cases are usually placed on the floor, your computer runs the risk of becoming a real storehouse of dust, dirt and wool from your pets.
3. The system fan, located inside the chassis, at the bottom of the chassis, pumps air in, while the power supply at the top of the chassis blows that air out. Typically, this arrangement provides sufficient ventilation, unless the hard drives are pushed too far back to obstruct the airflow from the system fan to the power supply.
4. The fan of the system unit is located below or above the power supply and blows in the same direction. This is not bad because the fans don't interfere with each other. However, it would be much better if there was a third fan at the bottom of the front of the case to help organize proper air circulation.
How can you change the direction of the system fan? For example, to make it work for blowing, not blowing? If you answered simply - "turn it the other way" - then you are absolutely right!
The air flow should also cool the computer's hard disk, for this it will be enough that there is free space around the disk - a few centimeters in each direction. In this case, the temperature of the hard drive case will not exceed 45 ° Celsius, and if the cooling is poor, you can burn yourself against the case. If you notice that your hard drive has started to work very slowly, while slowing down the operation of the entire system, overheating may be the cause.
The platters of the hard drive are made of a material that is resistant to heat, and the main problem is that all the heat goes to nearby materials that are prone to heat. It should also be borne in mind that the air circulating inside carries the heat away, but only if there is enough space for circulation. If the air is motionless, then the heat will slowly dissipate in it in all directions.
In general, for most hard drives, temperatures around 50 ° C are critical, which dramatically increases the likelihood of damage or data loss on the hard drive. Therefore, if your hard drive is actively used, it is recommended to install a special small fan on it. These devices are very simple and inexpensive.
Let's move on to the central processor. This is the hottest part of the system unit. Currently, almost all processors "grow" a real forest of aluminum columns or petals. It is a heatsink that draws heat from the processor and dissipates it into the air. The radiator can be passive if there is no fan on it. But if there is one, then we get an active radiator, in other words - a cooler. In modern systems, you should not rely on a radiator alone. It's like trying to cool off on a hot summer day, snuggling up against a cold, turned off central heating battery - it's chilly in one place, but there is no effect elsewhere.
The connecting link between any heatsink and the processor is a special thermal paste or hot glue, which fill any microroughnesses, forming a tight contact between the contacting surfaces of the processor and the heatsink. Thermal paste has a high thermal conductivity, thereby helping to better dissipate heat from the processor.
ATTENTION... Never use a cooler if it sits unevenly on the processor and the heatsink does not have tight contact with the processor surface!
In many BIOSes it is possible to view the readings of the thermal sensors installed in the system unit. If the processor temperature reaches a critical value, the motherboard will issue a warning signal through the system speaker. And if the temperature is exceeded, it can even automatically turn off the computer.
It should be noted that such parameters of the motherboard are usually disabled by default. And if you want to use them, you have to enable the appropriate BIOS settings yourself. Before doing this, it is highly desirable to know what temperature is critical for your processor. in the first models it was only 65 °, and many modern processors work quite confidently at 100 ° and even slightly higher.
When you install a good cooling system, without experimenting with liquid nitrogen or freon (this is not a joke, such systems actually exist), then the usual temperature regime of an unclocked processor will not go beyond 40 ° Celsius. True, this will not apply to modern computer games - under such a load, processors heat up much more.
However, even fairly good cooling systems sometimes cannot fit into the system unit. For example, the processor of a modern graphics card is usually quite hot. But since it is located on an AGP or PCI-EXPRESS card, it is not always possible to install a large cooler on it - it simply does not fit. Even if suddenly, you manage to install this cooler, then most likely difficulties will begin with establishing the movement of air flows.
If you are considering changing a processor cooler, you will come across the following classification: sleeve bearing fans, consisting of a rotor that is suspended inside a metal bushing soaked in durable grease or coated with Teflon. Lubricated coolers are cheap and quiet, but less durable, and Teflon fans last longer, but are therefore expensive. The middle ground you need is ball bearing (rolling bearing) fans, which are even more durable as the contact surface between the mechanism parts is reduced. Only they have one unsolvable problem that you have to put up with - they are the noisiest. In addition, you should pay attention to the material from which the cooler radiator is made. Aluminum radiators are the cheapest, but also the least efficient. But copper, although slightly more expensive, work much better. Copper radiators with gold plating are even more effective, but they are, of course, the most expensive.
The main unit for measuring the efficiency of any fan is cubic feet per minute (CFM). The average system fan drives 40 CFM through it, and the PSU fans are even smaller. Conventional processor fans pump 4 CFM, but cool cooling systems, which cost quite reasonable money, raise this figure to 40 CFM.
Many will ask, how can I cool the central processor now without buying anything at all? Think, maybe you can rearrange the internal devices so that the following conditions are met:
- 1. Internal devices should not hang over the processor, obstructing air movement.
- 2. All internal devices must be spaced sufficiently apart from each other so that they do not themselves become a source of hot air.
- 3. No device should block air from the system fans to the CPU cooler.
- 4. All wires inside the system unit, cables, loops, etc. must not impede the free movement of air inside the case.
And finally, one more parameter that you should pay attention to when buying a fan is the speed. The higher this number - the faster the fan rotates - the better it cools. But at the same time there is also more noise from it.
Cooling theory
So, a little theory. It is known from the physics course that any conductor through which an electric current flows generates heat. This means that absolutely all components of the computer, from the central processor to the power wires, heat the surrounding air. The amount of heat released by one or another computer component directly depends on its power consumption, which, in turn, is determined by many other factors: if we are talking about a hard disk, then the power of the electric motor and controller electronics, and if about a processor or another chip, then the number elements integrated into it and the technological process of its production. This is the physics of our world, and there is no getting away from it. But no one has yet come up with the idea to glue radiators on electrical wires and blow, say, internal modems! This is because different components of the computer affect the temperature in the case in different ways, and if such a "cold" device like a modem does not require any additional cooling, then we pay too much attention to the same video card, therefore, they put huge ones on modern motherboards. coolers, sometimes even with two fans.But first of all, let's repeat what a cooler is. A cooler (from the English Cool - cold) is a device for cooling something. The main task of any cooler is to reduce and maintain the temperature of the cooled body at a given level. And depending on the type of the cooled device, be it a transistor, chip, processor or even a hard drive, different types of coolers are used. In our concept, the cooler has strengthened itself as a "big piece of iron with a propeller", and the larger it is, the better it is. However, coolers can be more complex devices that cost hundreds of dollars. Typically, coolers used in computers consist of a fan, heat sink, and mount.
Radiators
Radiator (from the English. Radiate - to radiate) serves to remove heat from the cooled object. It is in direct contact with the object to be cooled, and its main function is to take on some of the heat generated by the body and dissipate it into the surrounding air. As you know, again from the physics course, an object gives off heat only from its surface, which means that in order to achieve the best heat dissipation, the cooled object must have as large a surface area as possible. In today's radiators, the surface area is increased by installing more fins. The heat from the cooled object passes to the base of the radiator, and then it is evenly distributed over its edges, after which it goes into the surrounding air, and this process is called radiation. The air around the radiator gradually heats up and the heat exchange process becomes less efficient, so the heat exchange efficiency can be increased by constantly supplying cold air to the radiator fins. For this, fans are used today. But we will talk about them a little later.The radiator must have good thermal conductivity and heat capacity. Thermal conductivity determines the rate at which heat spreads through the body. For a radiator, the thermal conductivity should be as high as possible, because often the area of \u200b\u200bthe cooled object is several times smaller than the area of \u200b\u200bthe base of the radiator, and with low thermal conductivity, the heat from the cooled object cannot be evenly distributed over the entire volume, along all the edges of the radiator. If the radiator is made of a material with high thermal conductivity, then at each point the temperature will be the same, and heat will be released from the entire surface area with the same efficiency, that is, there will be no situation when one part of the radiator is hot, and the other remains cold and will not give off heat to the surrounding air. Heat capacity determines the amount of heat that needs to be imparted to the body in order to raise its temperature by 1 degree. For radiators, the heat capacity should be as high as possible, because when it cools down by one degree, the body gives off the same amount of heat. The heat capacity and thermal conductivity of a radiator depend on the material used to make it.
Thermal material table
As you can see, it is most profitable to use two materials for the manufacture of radiators: aluminum and copper. The first one is due to its low cost and high heat capacity, and the second one is due to its high thermal conductivity. Silver is too expensive to be used to make radiators, but even if you don't take into account its high price, due to its good thermal conductivity, this metal is best used for making only the bases of radiators.
The design of the radiator is also important. For example, the ribs can be set at different angles to the air flow. They can be straight along the entire length of the radiator, or cut across, they are thick and burr if the radiator is made using extrusion technology, or thin and smooth if it was cast from molten metal. The ribs can be flat, bent from plates and pressed into the base. A radiator can generally be needle-shaped, that is, instead of ribs, it can have cylindrical or square needles. Today it is known that in terms of the design of the fins, needle radiators show themselves best.
Thermal interface
Radiators adjoin their base to the object to be cooled, and heat from it to the radiator passes only through the surface of their contact, so we must strive to make it as large as possible. But even the usually available contact area (for example, the surface of the processor core) must be used one hundred percent. The fact is that when two surfaces touch, the smallest cavities filled with air remain between them. This cannot be avoided, and no matter how flat and smooth the surface of the radiator may seem to you, it still has cracks and cavities where air collects. Air conducts heat very poorly, and therefore the cooling efficiency will be significantly lower than the capabilities of the radiator.To get rid of air cushions and increase cooling efficiency, various thermal interfaces are used. They have high thermal conductivity and, due to their fluidity, fill all the irregularities of the radiator base. As a result, the places where previously there was air in our way are now filled with a material that conducts heat well, and the radiator is already working at maximum efficiency. Thermal interfaces come in various types, thermal paste or conductive spacers. The gaskets are rubber-like polymer plates applied to the base of the radiators. When heated, they change their state of aggregation and, softening, fill in all the irregularities. Now thermal pastes are supplied with the vast majority of branded coolers. More often, thermal paste is simply put into a box with a cooler in a syringe or a small plastic bag. But it happens that it is already applied to the base of the radiator. In this case, it will only be enough for one or two installations, since it will be more difficult to assemble it from a cooled chip or processor than to buy another bag of paste. When choosing a thermal interface, I would recommend using thermal paste, not thermal pads. The high fluidity of thermal pastes allows them to better fill all the irregularities of the radiator, and due to the use of materials such as silver or aluminum in their composition, they have a higher thermal conductivity. Today on sale you can find thermal pastes with 90% silver content. And although silver is an excellent electrical conductor, manufacturers guarantee that the thermal grease does not close the contacts of the elements of the board or the device on which it is applied, but they still recommend not checking the insulating properties of their product and, if possible, avoiding getting thermal grease on the electrical components of the computer.
Fans
The fans provide a continuous flow of air to the radiator, converting the less efficient radiation process into the more efficient convection process. Convection is a heat exchange process that differs from radiation in that the cooling air is constantly in motion. In active coolers, it is forced into the radiator and, when heated, dissipates in the environment. With the use of a fan, the cooler becomes much more efficient, and the temperature of the cooled object can drop twice, or even more, depending on the fan performance. Fan capacity is its main characteristic, measured in the number of cubic feet of air distilled by it per minute, abbreviated as CFM (Cubic Feet per Minute). It mainly depends on the fan area, its height, the profile of the blades and their speed. The larger these values, the more air the fan can distill, and, accordingly, the more efficient the cooling will be. Today, fans for computer coolers do not have the ability to infinitely increase either the size or the rotation speed of the impeller. It is clear that a fan larger than 80 mm is already difficult to fit into the case, and the propeller speed directly affects its noise level. In addition, a larger fan will have to have a more powerful and more expensive electric motor, which will affect its cost.All fans used in computers today are powered by direct current, most often 12V. They use three-pin Molex connectors (for Smart fans) or four-pin PC-Plug connectors to connect to power.
A Molex connector has three wires: black (ground), red (plus), and yellow (signal). The PC-Plug has four wires: two black (ground), yellow (+12 Volts) and red (+5 Volts). Molex connectors are installed on motherboards so that the system itself can control the fan speed by supplying different voltages to the red wire (usually from 8 to 12 V), and change it if necessary. Through the yellow signal wire, the motherboard receives information from the fan about the rotational speed of its blades. Today, this has become very relevant, since a fan that stops on a processor cooler can damage the processor. Therefore, modern motherboards make sure that the fan is always spinning, and if it stops, then they turn off the computer. Connecting via Molex has one drawback: it is dangerous to connect fans with a power consumption of more than 6 watts to motherboards. The PC-Plug connector will withstand tens of watts, but when connected to it, you will not be able to find out if your fan is working or not. Today, more and more fans are bundled with PC-Plug - Molex adapters to connect them to the power supply, or even both connectors at once: PC-Plug and Molex, to receive power from the computer's power supply, and communicate to the motherboard via the Molex signal wire about the speed of the motor.
Also fans can have different types of rotor suspension. For this, sleeve bearing or Ball bearing are used. The fan can have one or two bearings, and sometimes they combine different types - Sleeve and Ball. The most reliable are fans with rolling bearings (conventional ball bearings). Manufacturing companies promise them continuous operation for 50,000 hours, which is more than five years, while those that use plain bearings promise to live no more than 30,000 hours, about three and a half years. Today there are already fans with ceramic bearings, which are promised almost immortality - 300,000 hours of continuous operation, and this is thirty-six years! However, on the one hand, the declared fan lifetimes are very rarely true, and often they must be divided by two or even three, and on the other hand, believe me, the computer will not live thirty-six years. It is worth reckoning that an ordinary fan can last a year or two. Then it starts humming, and it needs to be lubricated, but even lubrication will solve the problem only for a while, and soon the fan will have to be replaced with a new one.
Some modern fans have automatic speed control, depending on the ambient temperature or the temperature of the radiator. We will tell you about one such at the end of the article. In almost all of them, the temperature sensor is located directly on the fan itself and may not reflect the real temperature of the cooled object. That is, when the processor temperature rises, a cooler with such an automatic fan can only increase its speed after a couple of minutes. Another thing is fans with stop alarms installed on them. When the rotor speed drops below a certain limit, a special electronic unit on the fan wire emits a loud squeak, and you know for sure that it's time to turn off the computer and replace the cooler.
Passive coolers
Passive coolers are ordinary radiators installed on a cooled object. They remove heat only by radiation, if they are not blown by any computer fans, and are used to cool low-power and small-sized elements, for example, memory chips or transistors. Radiators are installed today on video cards, some motherboards, where there are still no full-fledged coolers, memory modules, and indeed practically everything that has to be cooled, and even on central processors, if they have low power.
A special case of a passive cooler is a heat distributor. It looks like a "bald" radiator made from a plate, without edges and with a small surface area. Heat spreaders are used today to cool system memory. In particular, Thermaltake produces special kits for DDR SDRAM DIMM modules. The disadvantage of heat distributors, like passive coolers, is their low efficiency.
Active coolers
Coolers that work by convection are called active. Simply put, it is a radiator with a fan installed on it. They are most often used to cool processors. And today, when we say the word "cooler", we mean, first of all, just them. Active coolers are used almost everywhere cooling is required, replacing conventional radiators. The advantages of such cooling can be called a significantly higher efficiency compared to conventional radiators. Active coolers are able to cool hot processors while being small. But fans are always a source of noise in computers and sometimes vibration. Therefore, they only need to cool the very hot elements, otherwise it will become unbearable to work behind a noisy machine. Another drawback of active coolers is that they are short-lived. The fan blades rotate, and sooner or later the bearings on the rotor will fail and it will stop. Naturally, in this case, the cooled element will overheat and, possibly, fail. But more often than not, the fans begin to hum loudly before stopping, so you will be warned in advance.
Now that we have figured out the basics of computer cooling, we can move on to looking at the heat sources in the computer and how to cool them.
What heats up in the computer and how does it cool
Well, having an idea of \u200b\u200bcoolers, now let's get a picture of what is heated in computers, and how it should be cooled (if necessary). We'll start with the most basic element of any PC - the central processing unit. Today, special attention is paid to cooling processors, and therefore every manufacturer of PC coolers must have in their assortment CPU coolers.Processors
If you do not consider server and laptop computers (including laptops), then today in personal computers processors are used by two manufacturers: Intel and AMD. They use three main platforms: Socket 370, Socket 478, and Socket 462 (Socket A). The platform designation numbers indicate the pin count for each processor. Naturally, all these standards are not compatible with each other, and you cannot install Pentium III for Socket 370 into a motherboard with any other socket. Until recently, the Socket 423 standard for the first Pentium 4 was also widespread, but with the arrival of the more modern Socket 478, it almost disappeared and is now being successfully forgotten. Each type of processor has its own cooler standards.
Socket 370 uses Intel Pentium III, Intel Celeron processors (except for new ones for Socket 478) and VIA C3. AMD processors (Duron, Athlon based on Thunderbird, Palomino and Thoroughbred) use Socket A. Coolers for Socket 370 and Socket A are almost compatible with each other. More precisely, we can say that they are fully compatible, but this does not mean that you can install a cooler for Athlon on Pentium III. The fact is that although the Socket 370 and Socket A sockets have the same dimensions, the standards according to which AMD recommends building motherboards differ from Intel's. First of all, look at the photo. Socket A has three teeth in the front and in the back for attaching a cooler. Initially, it was assumed that more powerful coolers would be installed on Athlon processors, which would require a more rigid mount, and one tooth could break under the cooler spring. In addition, AMD recommended that motherboard manufacturers leave the so-called free area to the left and right of the socket. This zone should not contain any elements that could interfere with the installation of rectangular coolers longer than 55 mm (slot width). Thus, Athlon and Duron processors can be equipped with 60x80mm coolers as high as your case allows. Of course, Pentium III will hardly have such large coolers, but again it depends on the motherboard.
In addition, many Athlon / Duron motherboards have four holes around the socket. This is another way of attaching the cooler - not to the socket, but to the motherboard. On the one hand, it is more convenient, since the cooler will not fall off after breaking off a tooth, and on the other hand, to replace it or upgrade the processor, you will have to remove the motherboard. Good or bad, but recently AMD stopped requiring four holes in the free zone near the processor socket, and all future coolers will be attached only to it, and not to the motherboard.
Athlon processors generate up to 73W of heat when not overclocked. For powerful servers, such heat dissipation of the processor is common, but for desktop computers it is a lot, and besides, the processor core area is constantly decreasing, therefore coolers for modern processors actively use copper in their radiators. And on sale you can see coolers not only with aluminum radiators, but also with a copper base, or completely copper. Some manufacturers, trying to increase the efficiency of coolers, also cover the copper with nickel, silver or other materials with high thermal conductivity. Fans on such coolers are usually 60x60x25 mm, although now 70mm and 80mm models are widely used. They have a lower rotational speed and are much quieter.
| CPU | Heat dissipation, W |
|---|---|
| AMD Duron 1100 | 51 |
| AMD Duron 1200 | 55 |
| AMD Duron 1300 | 57 |
| AMD Athlon Thunderbird 1400 | 73 |
| AMD AthlonXP (Palomino) 2100+ | 72 |
| AMD AthlonXP (Thoroughbred) 2600+ | 68.3 |
In the case of coolers for Socket 370, everything is much simpler: they all cling to two teeth of the socket and have dimensions that do not exceed the dimensions of the socket. Usually from 50x50 to 60x60 mm. The heat dissipation of Pentium III processors is approximately two times less than that of Athlon, therefore it is easier to cool them, and coolers with all-aluminum radiators or with a copper base are most often used on Pentium III. They are cheaper than completely copper ones, which, moreover, are not necessary.
If we continue talking about Socket 370 and remember about VIA C3 processors, then we can completely forget about coolers. The point is that VIA C3 has a reputation of being "cold" processors, because they generate too little heat and can work with passive coolers - ordinary heatsinks, or very simple coolers. For them, heat dissipation is not a problem, and therefore computers based on them are very quiet.
Today it is more profitable to produce coolers for Intel Pentium 4 and Celeron processors for Socket478. The fact is that the market for Athlon coolers is already quite saturated, and besides, the prices for computers with AMD processors are not high, and not every user is ready to pay dearly for a good cooler. With Pentium 4, the situation is completely different, since they are much more expensive than competitors from AMD, and coolers costing several tens of dollars can be sold on the high-performance processor market.
In computers with Pentium 4 and Celeron processors for Socket 478, the cooler is attached to a special rack on the motherboard. It is believed that Pentium 4 processors do not overheat at all. It is fundamentally wrong, and the first Pentium 4s really warmed up less than their Athlons, but now the power consumption of a 2.8 GHz Pentium 4 is around 64 W, while a 3.0 GHz Pentium 4 promises to require up to 80 W. Of course, the modern technological processes and design of the Pentium 4 with a built-in heat distributor help it better fight heat generated, but just like Athlon it requires a large cooler. True, boxed versions of processors are already supplied with coolers, but if necessary, you can find a wide range of coolers for Pentium 4 in stores.
Coolers for Socket 478 have, basically, one type of fastening: with two steel brackets they cling to the plastic stops of the motherboard and firmly press against the processor surface. Sometimes the motherboard bends slightly from too strong cooler springs, but by and large it's not a big deal. For computers using Pentium 4 in low or server chassis, there are coolers that are attached to the motherboard without the need for racks around the processor.
As in the case of some coolers for Athlon, in them the mount goes through the holes in the motherboard (for this you have to remove the standard cooler holders from it) and are fixed on the top of the processor. In this case, much less physical activity is applied to the board. Unfortunately, such coolers are not widely used.
Coolers with different heatsinks are produced for Pentium 4. There are both pure aluminum and copper bases, or completely copper. Fans for such coolers are usually quiet, because their low performance is compensated by the large size of the heatsinks. Although, loud models are also quite common among coolers for Socket 478.
Cooler (from the English cooler) - literally translated as a cooler. In essence, it is a device designed to cool the heating element of the computer (most often the central processor). The cooler is a metal heatsink with a fan that drives air through it. Most often, the fan in the computer system unit is called a cooler. This is not entirely correct. A fan is a fan, and a cooler is exactly a device (heatsink with a fan) that cools a specific element (for example, a processor).
The fans installed in the case of the computer system unit provide general ventilation in the case, the intake of cold air and the output of hot air. Thus, there is a general decrease in the temperature inside the case.
The cooler, unlike case fans, provides local cooling of a specific element that gets very hot. The cooler is most often installed on the central processor and video card. After all, the video processor heats up no less than the CPU, and sometimes the load on it is much stronger, for example, during a game.
The power supply also contains a fan, which simultaneously serves both to cool the heating elements in the power supply, as it blows air through it, and for general ventilation inside the computer. In the simplest version of a PC cooling system, it is the fan inside the power supply that ventilates the air inside the entire case.
Which way should the fans rotate in the case
So, let's consider the ventilation and cooling scheme of the computer. After all, many beginners, when assembling a computer on their own, have the question "Where should the fan blow" or "In which direction should the cooler turn". In fact, this is really important, because properly organized ventilation inside the computer is the key to its reliable operation.
Cold air is supplied to the housing from the front lower part (1). This should be taken into account when cleaning your computer from dust. It is imperative to vacuum the place where air is sucked into the computer. The air flow gradually warms up and rises upward and already hot air is blown out through the power supply (2) in the upper rear part of the case.
In the case of a large number of heating elements inside the case (for example, a powerful video card or several video cards, a large number of hard drives, etc.) or a small amount of free space inside the case, additional fans are installed in the case to increase air flow and improve cooling efficiency. Better to install fans with a large diameter. They provide more airflow at lower rpms and are therefore more efficient and quieter than smaller diameter fans.
When installing fans, take into account the direction in which they blow. Otherwise, you can not only not improve the cooling of the computer, but also worsen it. If you have a large number of hard drives, or if you have drives operating at high speeds (from 7200 rpm), you should install an additional fan in the front of the case (3) so that it blows through the hard drives.
In the presence of a large number of heating elements (powerful video card, several video cards, a large number of boards installed in the computer) or if there is not enough free space inside the case, it is recommended to install an additional fan in the upper rear part of the case (4). This fan should blow air out. This will increase the airflow through the case and cool all internal components of the computer. Do not install the rear fan so that it blows inside the case! This will disrupt the normal circulation inside the PC. On some cases it is possible to install a fan on the side cover. In this case, the fan must rotate so that it sucks air into the case. In no case should it blow it out, otherwise the upper part of the computer, in particular the power supply unit, motherboard and processor, will not be sufficiently cooled.
Which direction should the fan on the cooler blow
I repeat that the cooler is designed for local cooling of a specific element. Therefore, the total air circulation in the enclosure is not taken into account here. The fan on the cooler must blow air through the heatsink, thereby cooling it down. That is, the fan on the processor cooler should blow towards the processor.
On some cooler models, the fan is installed on a remote radiator. In this case, it is better to place it so that the air flow is directed towards the rear wall of the case or up towards the power supply unit.
On most powerful video cards, the cooler is a radiator and an impeller that does not blow air inward from the top, but drives it in a circle. That is, in this case, air is sucked in through one half of the radiator, and blown out through the other.
