Sooner or later you will have to face the need to replace the computer power supply. The main thing is not to panic. I want to reassure you right away - there is nothing wrong with this. When you buy a computer for the first time, you most likely choose the case and operating system, and pay almost no attention to the rest. This is exactly what sellers use. Cheap cases also contain the cheapest power supplies, which use components that are not of the best quality. And after a year and a half, these power supplies simply burn out.
In the future, of course, you will already know that it is best to assemble a computer yourself or select an assembly that meets your needs. Well, for now we will correct what is there.
And so, you need to replace the computer's power supply, namely the processor unit. What is needed for this?
The first thing, of course, is to buy the power supply itself. ? When purchasing, pay attention to whether the power supply has a switch. If not, then this is most often the cheapest, and not very good block. Although there are exceptions, it is better not to take risks, but to take a slightly more expensive, but more reliable one. Ask the seller if it makes a lot of noise?
Among the cheap power supplies, there are those that make the whole table shake when they work, and they make a strong humming noise. A good, high-quality power supply is much heavier than a cheap one due to more components and a thicker casing.
If you work on a computer at night, and even in the same room with sleeping relatives, then very soon they will have a desire to kill your computer, and maybe you in addition. It’s better not to take risks, and take pity on the nerves of your family.
When my daughter had such a noisy computer (and she likes to work on it at night), I had to pull a pillow over my head. Imagine what it was like for me in the heat.
Therefore, choose a power supply that is a little more expensive, but better. If you like to play games or do graphics, then choose a computer power supply more powerful. Read on the Internet which companies produce good models. Better yet, what models don’t need to be bought.
Now let's see What is a power supply computer.
Here's an iron box with a bunch of colored wires. There is a switch on the side next to the power cord connector. On top, under the spiral mesh, there is a cooler (in Russian - fan). In the system unit case it will be at the bottom.
Look at how the old power supply is installed.
1. Cable for connecting the power supply to the motherboard;
2.The second cable to connect to the motherboard;
5. Cable for connecting a hard drive and a CD or DVD IDE drive;
6. Cable for connecting a hard drive and a SATA CD or DVD drive;
7. Cable for connecting a Floppy drive, card reader, or additional power to a video card;
For the first time, you can make tags from paper and tape. This will give you confidence that you are doing everything right. It's better not to rely on your memory. In the future, you will already know what to connect and where, but for now it’s better to play it safe.
Be careful and careful with any remaining unconnected cables.
Tie them carefully to the harness of other wires, so that they do not dangle and do not touch other parts with the connectors. Otherwise, when moving the computer, one of the connectors may short out something.
After you have installed the power supply and connected all the necessary connectors inside and outside the system unit, you can turn on the computer. Just don't put your hands inside the case. If everything is done correctly, the computer should start.
The need to replace the power supply arises quite often. You may encounter such a need due to the desire to upgrade your computer and increase its power or due to problems with a component, for example, when it burns out. The following instructions will allow you to quickly replace the power supply on the computer on new. Even if you are a novice user, just follow each step carefully and you will complete this task:
When connecting the motherboard to a new component, please note that the board can be connected using 2 wires from the power supply. It is worth considering that different plugs are used to connect hard drives of old and new models. To connect new SATA hard drives, you need to use cables that have the same name. Connecting old hard drives is similar to disk drives. All wires must be connected in the same order. It is worth noting that connecting the power connector to the motherboard may require some effort. The advantage of the design of such connectors is that the user is protected from incorrect connection of wires. If you are unable to connect the connector, unscrew it and try to insert it again. It is important to install the cables so that they do not touch the fan or its blades. Unused wires should be secured to the inside of the system unit.
9. After connecting all the wires, replace the cover from the system unit and secure it with the mounting bolts. Then connect all the necessary components externally, including wires from the mouse, monitor, network cable, keyboard, etc.
10.Check the functionality of the computer with the new system unit by turning on the PC.
Do you want to replace the power supply?
One day I received a letter from a “teapot”, in which the question was asked: when is it necessary to change the power supply? The question is correct and here's why.
Very often, the user encounters such a problem as a system freeze. Moreover, “freezing” is “dead”, that is, the computer can be brought out of its stupor only by pressing the “Reset” button. And then the question arises: why, exactly?! After all, the system doesn’t complain about anything, there are no viruses or Trojans, and my software is the most super-duper! Why the hell does the system hang then? Then the user goes to an online forum and tries to get to the bottom of the truth. What does he hear in response? Oh, on online forums the “teapot” (and not only him) receives a lot of “practical” advice. For example, online gurus (“gurus” are dudes who consider themselves higher than the sky and supposedly have transcendental information about the essence of the universe) often ask about the configuration of your hardware. I never understood what the configuration has to do with it, if a person describes specific symptoms of the problem: they say, the computer often “freezes” simply after starting, or during some simple actions, for example, playing video or audio. Explain to me, dear “gurus”: what does the computer configuration have to do with it? That's right: nothing to do with it! Why ask then?
Computer configuration is only necessary when you want to update something - that is, to “upgrade” some node, for example, a video card. Then - yes, configuration is needed so as not to make a mistake: in matters of “upgrade” there are generally many subtleties and nuances in the issue of equipment compatibility!
So let's continue. What does this have to do with the power supply? But here's what it has to do with it. Each power supply has its own safety margin. Over time, for some reason, this safety margin runs out. The most common cause of power supply depletion is the lack of a voltage regulator! What does the stabilizer have to do with it? How - what does it have to do with it?! Who told you that the voltage in your outlet is constantly at the “height” of 220 volts? Thanks to our most “advanced” power supply system, the voltage in the outlet can “jump”, both negative and positive. Did you know that a change of even a few volts has a detrimental effect on the power supply unit, and the system as a whole? And okay, if the voltage in the network drops: what if, on the contrary, it increases? Yes, not by a couple of volts, but by a couple of tens? And if at this moment your power supply does not burn out, then many of its parts will burn out quite nicely. Here's "St. George's Day": will the burnt parts last long? I hope this is all clear.
As for the question “how often should you change the power supply,” then everything is simple. If you do not have a voltage stabilizer (which is very sad, because it prolongs the life of the power supply), then change the power supply at the moment when the number of “freezes” per day has reached two or three. At least this is how I approach this issue, since I only have one voltage stabilizer for two computers. And believe me: not all hang-ups are due to some kind of global system failure! And in general: most problems are solved by simply replacing the power supply. For example, your Internet, online video, or game began to slow down. Viruses have nothing to do with it: just replace the power supply.
I hope you are now armed enough to make the right conclusion before taking your hardware to a service center: replacing the power supply will save you from problems!
Good luck!
One of the important components of a modern personal computer is the power supply unit (PSU). If there is no power, the computer will not work.
On the other hand, if the power supply produces a voltage beyond the permissible limits, this can cause failure of important and expensive components.
In such a unit, with the help of an inverter, the rectified mains voltage is converted into high-frequency alternating voltage, from which the low voltage flows necessary for computer operation are formed.
The ATX power supply circuit consists of 2 nodes - a mains voltage rectifier and a voltage converter for the computer. The mains rectifier is a bridge circuit with a capacitive filter. A constant voltage of 260 to 340 V is generated at the output of the device.
The main elements of the voltage converter are:
In addition, the converter includes a standby voltage power supply, amplifiers for the control signal of key transistors, protection and stabilization circuits, as well as other elements.
The inverter includes two power transistors operating in switching mode and controlled using signals with a frequency of 60 kHz coming from a control circuit implemented on the TL494 chip.
A pulse transformer is used as the inverter load, from which the voltages +3.3 V, +5 V, +12 V, -5 V, -12 V are removed, rectified and filtered.
The causes of malfunctions in the power supply can be:
Malfunctions usually lead to the fact that the computer system unit stops starting or turns off after a short period of operation. In other cases, despite the operation of other units, the motherboard does not start.
Before starting repairs, you need to finally make sure that it is the power supply that is faulty. In this case, you first need to check the functionality of the network cable and the power switch. After making sure that they are in good condition, you can disconnect the cables and remove the power supply from the system unit case.
Before you turn on the power supply autonomously again, you need to connect the load to it. To do this, you will need resistors that are connected to the corresponding terminals.
In this case, the value of the resistance of the load resistors must be selected so that currents flow through the circuits, the values of which correspond to the nominal values.
The power dissipation of the resistors must correspond to the rated voltages and currents.
First you need to check the influence of the motherboard. To do this, you need to close two contacts on the power supply connector. On a 20-pin connector, these will be pin 14 (the wire that carries the Power On signal) and pin 15 (the wire that corresponds to the GND - Ground pin). For a 24-pin connector, these will be pins 16 and 17, respectively.
The serviceability of the power supply can be assessed by the rotation of its fan. If the fan rotates, the power supply is working.
Next, you need to check that the voltages at the unit connector correspond to their nominal values. It should be taken into account that, in accordance with the documentation for the ATX power supply, the deviation of voltage values for the -12V power circuit is allowed within ± 10%, and for other power circuits ± 5%. If these conditions are not met, you must proceed to repair the power supply.
After removing the cover from the power supply, you must immediately clean all dust from it using a vacuum cleaner. It is because of dust that radio components often fail, since dust, covering the part with a thick layer, causes overheating of such parts.
The next step in troubleshooting is a thorough inspection of all elements. Particular attention should be paid to electrolytic capacitors. The reason for their breakdown may be severe temperature conditions. Faulty capacitors usually swell and leak electrolyte.
Such parts must be replaced with new ones with the same ratings and operating voltages. Sometimes the appearance of the capacitor does not indicate its malfunction. If, based on indirect signs, there is a suspicion of poor performance, then you can check the capacitor with a multimeter. But for this it needs to be removed from the circuit.
Deterioration in thermal conditions inside the unit may be due to poor performance of the cooler. To improve performance, it must be cleaned of dust and the bearings lubricated with machine oil.
A faulty power supply can also be caused by faulty low-voltage diodes. To check, you need to measure the resistance of the forward and reverse transitions of the elements using a multimeter. To replace faulty diodes, you must use the same Schottky diodes.
The next malfunction that can be determined visually is the formation of annular cracks that break the contacts. To detect such defects, you need to carefully examine the printed circuit board. To eliminate such defects, it is necessary to carefully solder the places where cracks form (for this you need to know how to solder correctly with a soldering iron).
Resistors, fuses, inductors, and transformers are inspected in the same way.
If a fuse is blown, it can be replaced with another one or repaired. The power supply uses a special element that has leads for soldering. To repair a faulty fuse, it is removed from the circuit. Then the metal cups are heated and removed from the glass tube. Then select a wire of the desired diameter.
The wire diameter required for a given current can be found in the tables. For the 5A ATX fuse used in the circuit of the ATX power supply, the diameter of the copper wire will be 0.175 mm. Then the wire is inserted into the holes of the fuse cups and fixed by soldering. The repaired fuse can be soldered into the circuit.
The most common malfunctions of a computer power supply are discussed above.
Detecting and repairing more complex faults requires good technical training and more sophisticated measuring instruments, such as an oscilloscope.
In addition, elements that need to be replaced are often in short supply and are quite expensive. Therefore, in case of a complex malfunction, you should always compare the costs of repairs and the costs of purchasing a new power supply. It often happens that it is more profitable to purchase a new one.
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elektrik24.net
Repairing a computer power supply yourself is quite a difficult task. Having undertaken this, you should clearly understand which of the components requires repair. Also, you should understand that if the device is under warranty, then after any intervention the warranty card immediately expires.
If the user has little skills in working with electrical appliances and is confident that he will not make mistakes, then he can safely take on such work. You should remember to be careful when working with electrical appliances.
To create galvanic isolation, a transformer with a large number of windings is required. Based on this, a computer requires quite a lot of power and it is natural that such a transformer for a PC should be large and of considerable weight.
But due to the frequency of the current required to create the magnetic field, much fewer turns are required on the transformer. Thanks to this, when using a converter, small and lightweight power supplies are created.
The power supply is, at first glance, a rather complicated device, but if a minor breakdown occurs, then it is quite possible to repair it yourself.
Below is a standard power supply diagram. As you can see, there is nothing complicated, the main thing is to do everything one by one so that there is no confusion:
In order to begin repairing the power supply yourself, you should have the necessary tools on hand.
First you need to arm yourself with computer diagnostic tools:
To perform the repair itself you will also need:
Naturally, this is not so much for a complete renovation, but this is enough for home renovation.
So, armed with all the necessary tools, you can begin the repair:
In some cases, the power supply fails due to the microcircuit. Therefore, you should carefully examine its details. Particular attention should be paid to the fuse, transistor and capacitor.
Often, the cause of power supply failure is swelling of the capacitors, which break due to poor performance of the cooler. This whole situation can be easily diagnosed at home. You just need to carefully examine the top of the capacitor.
swollen capacitors
A convex cap is an indicator of fracture. In ideal condition, the capacitor is a smooth cylinder with flat walls.
To fix this problem you will need:
To prevent your computer from overheating, you should blow it regularly.
In order to check the fuse in another way, it is not necessary to unsolder it, but rather connect a copper wire to the contacts. If the power supply starts working, then it is enough to simply solder the fuse; perhaps it was simply moving away from the contacts.
To check the functionality of the fuse, just turn on the power supply. If it burns out a second time, then you need to look for the cause of the breakdown in other parts.
The next possible failure may depend on the varistor. It is used to pass current and equalize it. A sign of its malfunction are traces of soot or black spots. If such were found, the part must be replaced with a new one.
varistor
Note! A varistor is a computer part that is checked when it is turned on, so you need to be careful and attentive. Using a similar principle, each individual part is checked: diodes, resistors, capacitor.
It should be noted that checking and replacing diodes is not a very simple task. To check them, you should unsolder each diode individually or the entire part at once. They should be replaced with similar parts with the declared voltage.
If after replacing the transistors they burn out again, then you should look for the cause in the transformer. By the way, this part is quite difficult to find and buy. In such situations, experienced professionals recommend buying a new power supply. Fortunately, such a breakdown occurs quite rarely.
Another reason for PSU failure may be related to ring cracks that break contacts. This can also be detected visually by carefully inspecting the printed strip. You can eliminate such a defect using a soldering iron by performing careful soldering, but you must be good at soldering. If you make the slightest mistake, you can damage the integrity of the contacts and then you will have to replace the entire part.
ring cracks
If a more complex breakdown is detected, then excellent technical training will be required. Also, you will have to use complex measuring instruments. But it should be noted that purchasing such devices will cost more than the entire repair.
You should know that elements that require replacement are sometimes in short supply and not only are they difficult to obtain, but they are also expensive. If a complex breakdown occurs and repair costs exceed the price compared to purchasing a new power supply. In this case, it will be more profitable and reliable to purchase a new device.
After the reasons that brought the power supply out of operating mode have been eliminated, it must be checked.
The most basic operation is to turn on the computer to the network. But, by the way, this can be done without connecting a PC. It is enough to connect any load to the power supply, for example a CD-ROM, after which you need to short-circuit the green and black wires in the power supply connector and turn it on.
If everything is in order, then the fan and drive LED will immediately turn on on a working power supply. And naturally, the reverse reaction of the power supply (if nothing starts working), then the cause is not eliminated.
Once the serviceability of the device is confirmed, you can begin assembling the system unit.
Before you undertake independent repair of the power supply, you need to be fairly confident in your knowledge of electrical appliances:
In a vacuum, a power supply failure will not occur. If signs appear that indicate its malfunction, then before starting repairs, the reasons that led to its failure must first be eliminated.
Signs:
A faulty power supply cannot be missed, since problems begin with turning on the system unit (it does not turn on at all) or it turns off after several minutes of operation.
If at least one of the problems is noticed, you should think about eliminating the malfunction, otherwise, the computer may completely fail, and then you cannot do without the intervention of an experienced specialist.
Main problems:
Note! Power capacitors tend to hold a charge for some time; therefore, it is not recommended to touch them with bare hands after the power is turned off. Also, you should remember that when the power supply is connected to the network, you do not need to touch the stove or radiator.
If you repair the power supply yourself and do not have the necessary tools at hand, then first of all you will have to spend money on buying them. This amount can reach from 1000 rubles to 5000 rubles.
As for the power supply itself, everything depends on the parts that have become unusable. On average, repairs can cost up to 1,500 thousand rubles.
Please note: a used power supply in good condition can cost 2000 – 2500 rubles. This applies to models for older computers. Modern PCs are equipped with more expensive power supplies.
At a service center, a similar procedure can cost about the same amount. But at the same time, you should remember that a specialist always gives a guarantee for his work.
slarkenergy.ru
Problems with unstable voltage in AC networks are the scourge of domestic electrical networks, which leads to the failure of many household appliances. For example, a desktop computer. Both during operation and when switched off, this device is exposed to the negative effects of power surges. The thing is that the negative impact is mainly directed at the power supply, which still works even when the computer is turned off. And that means this is the most vulnerable place. That's why it most often fails. And here many ordinary people have a question: what to do: buy a new one or repair the computer power supply with your own hands?
Power supply for computer The question is actually posed very correctly. Everything will depend on how the computer is built. If the power supply is assembled from nameless parts (specialists usually call them non-name parts), then this is a cheap option that makes no sense to repair. It will be easier and cheaper to choose and purchase a new one. Although you can try to repair a computer power supply using it. Even if you don't succeed, it will be a good experience. So it's worth tinkering with it at your leisure.
But if your computer has a branded power supply, then replacing it with a new one will cost a pretty penny, so it makes sense to understand its configuration and circuitry and carry out the repairs yourself.
By the way, there is an easy way to check the functionality of the power supply. To do this, it must be disconnected from the motherboard. Simply disconnect the connectors of the wires leading from the block to the plateau. Connectors can be 20 or 24 pins (4 or 6). To check whether the unit is working, you need to short-circuit contacts 14 or 15 with each other (if the connector is twenty-pin) or 16 and 17 (if it is twenty-four pin). That is, green (sometimes gray) and black wires are connected to each other. Then the unit itself is connected to the network through an outlet. If the cooler fan starts working, then everything is in order, it is not the cause. We need to look for other faults.
Computer power supply in the system unit So, let's start with a disclaimer that will determine the root cause of the question, how to repair a computer power supply? Remember that the power supply itself, unlike the computer, operates at 220 volts. Therefore, high-capacity capacitors are installed in his circuit. They accumulate tension that can be stored for a long time.
Do-it-yourself repair of any electronic device is based on working with a soldering iron. And if you don’t have much practice, then you should abandon this idea. After all, a computer power supply unit is a responsible device, on which it depends whether the computer will work or not.
Plus, you will have to figure out the diagram as events go, because you are unlikely to find an exact diagram, even on the Internet. There are schematic diagrams, but this does not mean that it will be exactly the same in your power supply. Therefore, everything will have to be done as the repair progresses.
Internal structure of the power supply First of all, you need to remove the cover and clean all the insides from dust. A thick layer of dust becomes a barrier that prevents temperature transfer from working parts. So this is also the reason for the failure of the unit.
Now pay attention to the fuse. Usually a 5 A part is installed here. This is a glass bulb with a thin metal thread running inside it. If there is no thread, then the fuse is blown and needs to be replaced. But sometimes there seems to be a thread present, so it’s worth checking the fuse. How?
The first thing you need to do is clean the inside of your computer from dust. Typically, power supplies contain capacitors with large capacitance. It is in them that tension accumulates. Therefore, these are the parts that most often fail (in 80% of cases).
The first thing that should catch your eye is swelling and leakage of electrolyte. If all this is available, then it is one hundred percent that the capacitor is not working.
Attention! Poor fan operation causes capacitors to swell. The thing is that the fan must cool the capacitors, which are heated due to the accumulation of voltage in them. Therefore, experts recommend periodically cleaning the fan bearings and cleaning the entire cooler.
But sometimes there are no visible defects in capacitors, so it is worth checking them with a multimeter to check the resistance. If the resistance is high (compared to the nominal value), then this indicates that there is a gap between the inner lining and the terminal. Experts call this situation a broken capacitor.
Swollen capacitors There are also electrolytic capacitors in the power supply circuit. They can also swell, but there is no point in replacing them with new ones, because you must first find the cause of their swelling and then replace them. Usually the cause is a failure of the voltage stabilization circuit. So until you figure it out, there is no point in changing electrolytic capacitors. It won’t help, they will still swell. But repairs to computer power supplies of this type can only be carried out by a specialist; you cannot do it yourself. Plus, you will need professional measuring instruments. So the best option is to take the power supply to a workshop. In this case there is no choice.
This is another part that can cause the PC power supply to malfunction. Pay attention to the design feature of the transistor. He has three legs:
So, to determine whether a part is working or not, you need to ring it with a multimeter. And here you need to know how to call. Dialing can only be done in two directions:
Transistors in the power supply If you change the polarity of the dial, then nothing will happen. The same applies to the direction between the collector and emitter. To correctly carry out the ringing, you need to connect the probe with the red wire to the base of the transistor, and the black wire to the collector or emitter. If the display shows an indicator within 650-800 mV, then everything is fine, the transistor is intact.
To check, you can ring the collector-emitter. Here the resistance should be infinite, the display will show one. If this transition is broken, the multimeter will emit a characteristic signal. But note that this is not necessary; other transitions also do not work.
As for diodes, these small devices are practically the same as transistors. That is, a transistor is two diodes connected in series, but with cathodes at one point. Therefore, ringing them is practically a test of the base-collector or base-emitter transition. The resistance indicators are exactly the same.
Transistor design What is the purpose of converting a computer power supply? That is, is it possible to replace some of its parts to improve the operation of the device? Some masters try to make some changes, and thereby achieve better results. We will not go into details of all the modifications, because we are talking about independent repairs. And some of them cannot be done with your own hands.
The simplest modification is to reinstall the capacitors that are built into the power bus. They are designed for a voltage of 5 V. So, the more voltage these devices can withstand, the better. It would be nice to install capacitors rated for 10 V in their place, but they are large in size, so they may not fit on the plateau. Therefore, it is still worth choosing a capacitor with a high voltage that would fit on the plateau, for example, at 6.5 V.
Attention! Replacing a capacitor depends on its correct installation on the plateau. Therefore, pay attention to the negative output strip. It is wide, vertical and light. So, the new device must be installed in exactly the same position so that the strip ends up in the old installation location.
The main requirement when repairing a power supply with your own hands is the ability to work with a soldering iron. So, if you have replaced all the failed parts, then the power supply should work. The easiest way to check this is to plug it into a power outlet. The cooler fan should spin. There is another more reliable option - check the main connectors for voltage with a multimeter. Their value should be 12 and 5 volts.
As you can see, repairing a power supply is actually a difficult process. Although if you figure it out and go through the diagram several times, changing first one device and then another, then you can already consider yourself a home craftsman. But the most important thing, as practice shows, is the ability to work with a soldering iron.
OnlineElektrik.ru
The power supply in a personal computer is one of the most important components. These devices differ not only in power, but also in design features. Before release, all models undergo a certain standardization procedure. The main elements of the blocks can be considered a transformer, a converter, and a rectifier. Additionally, depending on the modification, various cooling and protective systems are installed on the device.
Replacing the power supply is quite simple, and you can do it yourself without any effort. To do this, a person will only need a Phillips screwdriver from the tools. The unit is located in the personal computer case at the back side, where all the connectors are located. First of all, you need to unscrew the four nuts on the panel. After this, the unit will detach from the lid of the personal computer, but it is currently impossible to remove it. This is due to the fact that the block remains connected to the motherboard, hard drive, and CD-ROM. Therefore, before removing the device, a person is obliged to disconnect all contacts that prevent this.
When a power supply breaks down, the first thing you need to do is perform a general diagnostic to understand the cause of the problem. To do this, you need to disconnect the element from the personal computer. To do this, unscrew the four nuts that hold the protective cover of the device. This can be done using a Phillips screwdriver. Next, the lid must be carefully lifted up. In order for a person to have full access to all elements of the unit, it is important to disconnect the cooler of the device after removing the panel.
It is usually fastened with four nuts, and you can also deal with them using a Phillips screwdriver. Next, you should carefully inspect all components. In particular, it is important to pay attention to dark spots. When the system overheats, black spots usually remain. After this, you can disconnect the transformer and inspect the converter. If the integrity of the winding is not compromised, then the unit needs a more thorough check.
Many buyers choose an Asus power supply due to its high power. On average it is approximately 500 W. The cables of the models are mainly used of the non-modular type. On average, the best power supply from Asus costs around 3 thousand rubles. In this case, rectifiers are installed next to the converters, and their throughput is quite good. They have all standard connectors.
At a voltage of 3 V, the device can withstand an average load of 24 A. Separately, the operation of the filters should also be noted. They are installed in network type housings only and are located next to the rectifiers. The main problem with the units of the above company is considered to be overvoltage of the inductor. This is caused by the fact that the threshold voltage level increases sharply. As a result, the integrity of the winding is compromised. In order to replace the inductor, the emergency power supply must be removed from the personal computer.
Next, you need to unscrew all the nuts that hold the upper U-shaped cover. After this, you don’t even have to touch the cooler. In this case, the coil can be disconnected separately. At the same time, it is held on the microcircuit by just one contact. After replacing the element, the unit must be reassembled and inserted into the personal computer.
Samsung blocks are in great demand today. Modulators in almost all models are binary. Their important advantage is good signal conductivity. At the same time, the latency in the system is quite small. However, the Samsung power supply also has disadvantages. First of all, it should be noted a common malfunction that is caused by a conflict between the system and the converter. This process occurs due to the fact that the bandwidth in the device changes. In order to solve this problem, the unit converter must be replaced.
This is quite easy to do if you have a Phillips screwdriver on hand. In this case, the cooler in the unit will have to be disconnected. This way, the person will have full access to the converter. It is attached to the microcircuit using a special clamp. In order to remove it, you need to press on the small protrusions with your fingers on both sides. The converter will then be disconnected. Before installing a new model, the plate on which the part is located must be cleaned. Regular cotton wool is suitable for these purposes. Some experts additionally advise lubricating it with ethyl alcohol.
Repairing computer power supplies with your own hands if the input filter breaks is quite simple. To do this, you must first extract this element. It is usually located in the device near the rectifier. In some cases, the filter is connected to the converter. In order to check its performance, it is necessary to inspect its upper part. If dark spots are visible on it, then the element has been overloaded. In this case, the person is obliged to clean all contacts and fix the filter in its original place.
In order to repair computer power supplies with your own hands if the inverter breaks down, you need to have a Phillips screwdriver. The above element is located near the cooler. You can disconnect it by moving the plate that is located at its base. In some cases, manufacturers install two clamps in this place that are connected to each other. In this case, the inverter is disconnected with two fingers. Repair of the device in such a situation must begin with an inspection of the base. It is a flat plate to which the regulator is attached.
If there are any defects at the base, the element will have to be completely replaced. To do this you will need to purchase a similar model. In order to secure the inductor in its previous position, you must first lift the plate up. If there were two clamps there, then before installing the inductor they are moved to the side. After this, a protective cover is screwed onto the unit, and the device is placed back on the personal computer case.
It is quite difficult to repair computer power supplies with your own hands if the controller breaks down. The whole problem in this case is the presence of a large number of electrodes. When the system short-circuits, the controller is unable to operate properly. In order to clean contacts, many people recommend using an eraser. At the same time, you don’t need to put a lot of effort into it. If this does not help, then the controller is completely unscrewed from the rectifier and replaced with a new one.
This can be done using a screwdriver. In this case, it is important not to damage the microcircuit, since it is located quite close and is very vulnerable to mechanical contacts. Specialists replace the controller only with the participation of cotton wool. In this case, the lower part of the element must be thoroughly wiped. Ethyl alcohol is not recommended for use in this situation.
Repairing computer power supplies with your own hands, including replacing the cooler, is quite simple. To do this, you must first remove the side cover from the personal computer. Then the uninterruptible power supply unit is directly disconnected. Today, a wide variety of coolers are installed in it. However, they are usually mounted on the side wall. To remove the device, you need to use a screwdriver. In this case, there are usually four nuts on it.
After this, you can directly disconnect the cooler from the unit. However, it is important to ensure that its power cable does not interfere. It is best to disconnect it immediately in this situation. This can be done simply by lifting the port, which is located near the chip. After this, the cooler can be conveniently placed on the table for further work. First of all, it is important to remove the sticker, which is its additional protection. There may be a small rubber gasket underneath it. Depending on the design of the fan, it can cover the connecting rod or the rolling bearing.
In order to remove the bushing, it is necessary to remove the protective ring that holds it in place. After this, the bushing protrudes. At this stage, you need to make sure that the puck does not fall on the floor. The cooler is then cleaned with machine oil and must be reassembled in reverse order. After turning on the power supply, you need to check the operation of the fan and make sure it is working properly. If after all the above steps it makes any sounds, then the device was assembled incorrectly.
Repairing the PC power supply by replacing the inductor can only be done using a blowtorch. In order to get to the specified part, the block must be completely disassembled. Additionally, the inverter must be disconnected. The converter is removed from the chip last. The throttle for the block should be selected from a specific series. In this case, much depends on the power of the device. The contacts begin to be soldered precisely from the microcircuit side, and then the inductor is connected to the transformer. Subsequently, if the wiring is soldered incorrectly, the contacts can be reconnected.
Before repairing a PC power supply, the microcircuit must be inspected. In general, this part is quite complex in its design. Considering this, it is necessary to treat the microcircuit with special care. First of all, experts advise inspecting the resistors that are located next to the controller. In some cases, their contacts overheat. In general, you can check the functionality of the microcircuit simply by connecting a normal model.
The radiator in the unit breaks quite rarely, but such cases do occur. In this situation, it must be disconnected from the transformer. Only after this will a person be able to examine it. At this stage, only the base of the part is checked. In particular, it is necessary to inspect its platform for any defects. After this, the part is inspected from the top. If dark spots are visible on it, then the radiator has become unusable. To replace it, you need to purchase a similar product from the store. It is attached to the transformer, usually with a screw. However, much in this case depends on the manufacturer.
Repairing the unit in terms of inspecting the transformer is only possible if you disconnect the cooler in advance, since it will interfere in the future. After this, the transformer is inspected from the sides. If its contacts are dirty, then they need to be cleaned. A regular eraser is ideal for these purposes. However, alcohol-based wipes can also be used. If the specified procedure does not help in the operation of the unit, then the transformer needs to be changed.
Replacing the controller at home is very quick. The only tool required for this procedure is a Phillips screwdriver. The controller is attached to the transformer using only one clamp. It is quite easy to remove from the safety lock, and no great physical effort is required. Next, it is important to clean the metal part and wipe it with a dry cloth. After this, it is possible to connect a new controller model. When the unit is turned on, the device should operate quietly. If any noise appears, it means that the installed element is not suitable for the block according to its parameters.
Repairs to the unit regarding faults with rectifiers are carried out only in special workshops. However, it is also not possible to replace it at home. Considering all of the above, there is no need to try to remove the rectifier from the microcircuit. All this in some cases ends simply in the block breaking. Specialists using a soldering iron and tweezers can remove this device without damaging the board.
After inspecting the rectifier, it will be possible to decide its fate in the future. As a rule, the easiest way is to simply replace it with a new one. However, in this situation, the reason for its failure is taken into account. The rectifier itself does not break, and in parallel in the block their converter and transformer also fail. All this is a consequence of a sharp increase in the maximum voltage in the network.
Models from this company are currently actively sold out. The average cost of a power supply (market price) is around 3 thousand rubles. The power of a conventional model is around 500 W, and the device can hold a maximum load of 23 A. A common problem with these elements is considered to be the breakdown of the modulator. However, converters often fail due to overvoltage. In this case, the fans installed are usually reliable.
The Zalman company's power supplies have good reviews. Many models of this brand can boast a maximum power of 550 V. At the same time, the transformer can hold a maximum load of 25 A. A powerful power supply from Zalman costs about 3,200 rubles. In this case, rectifiers are installed broadband. In turn, coolers can most often be found without rolling bearings.
Their lubrication disappears quite quickly, and ultimately the uninterruptible power supply unit begins to operate noisily. In such a situation, it is more advisable to disassemble the cooler and replace worn parts if necessary. Burnout of the converter is also considered a common problem with the units of this company. This happens due to a banal increase in voltage in the electrical wiring of the house. As a result, the transformer inside the unit may additionally burn out.
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A computer's power supply unit (PSU) is a complex electronic device that provides power to all computer devices. As a rule, the power supply has several power connectors with different output voltages designed to power certain devices.
You can perform a preliminary check of the power supply without special instruments and without disassembling the power supply itself. The essence of the test is to check the power supply starting system, as well as checking the computer devices for possible short circuits.
Disconnect all power connectors from all devices on the system unit. To disconnect the motherboard power connector, you must first unlock it. Now manually start the power supply. To do this, you need to short-circuit two pins on the motherboard power connector with a wire or a paper clip (usually a green wire and any black one, less often there may be a gray wire instead of green). If the connector has pin markings, then the Power ON and GND pins should be shorted.
After this, the power supply should turn on, which can be checked by rotating the cooler of the power supply cooling system. If the power supply does not turn on, then it is faulty and its further repair should be entrusted to a specialist.
However, successfully turning on the power supply does not guarantee that it is working stably. In this case, first of all, it is necessary to check the system unit (PC) devices for a possible short circuit.
First connect the motherboard to the power connector and turn on the power supply; if it starts, then the motherboard is working. Now turn off the power supply and unplug the power cord. This is necessary to ensure that the power supply can be restarted manually.
Now connect other computer devices in series (hard drive, floppy drive, etc.) and turn on the power supply. If you do not find a fault, then the next step is to check the power supply itself. Well, if when you connect one of the devices, the power supply does not start, then most likely there is a short circuit in the power supply circuit of this device.
The power supply may work successfully, but the output voltage may be too low or too high, which will lead to instability of the computer. You can determine this by using a multimeter (digital voltmeter) and measuring the output voltage at the power connectors. On the multimeter, switch the handle to the position for measuring direct voltage (DCV) with a measurement limit of 20V.
Connect the black probe of the multimeter to the black wire of the power supply, this is our ground, and touch the second (red) one to the corresponding terminal of the power supply connector, that is, to all the others.
The output voltages of the power supply must be within acceptable limits: For the supply voltage +3.3V (orange wire), the permissible voltage deviation should not exceed 5% or from +3.14V to +3.46V.
For +5V supply voltage (red and blue wires), the permissible voltage deviation should not exceed 5% or from +4.75V to +5.25V.
For supply voltage +12V (yellow wire), the permissible voltage deviation should not exceed 5% or from +11.4V to +12.6V.
For a supply voltage of -12V (blue wire), the permissible voltage deviation should not exceed 10% or from -10.8V to -13.2V.
It is best to take measurements under load, i.e. when the computer is turned on.
Before troubleshooting the power supply, it must be removed from the computer. Lay the computer case on its side and unscrew all four screws securing the power supply. Carefully remove it from the case so as not to damage other computer devices and disassemble it by removing the casing. After this, remove all the dust accumulated inside using a vacuum cleaner.
Replacing the fuse
All power supplies have a similar design and functional diagram. At the input of each power supply there is a fuse, which is soldered into the printed circuit board, but there are also power supplies on which mounting sockets are installed, for the convenience of replacing the fuse. This is what needs to be checked first.
A blown fuse thread indicates either a short circuit or the power supply is operating under high load. Replace it with a similar one with the same response current or a slightly higher current (for example, if you have a 5 A fuse installed, then it can be replaced with 5.5-6 A - no more!). But, in no case should you install a fuse with a lower operating current - it will burn out immediately.
If you still encounter a fuse that is soldered into the printed circuit board. In this case, you can install a regular fuse suitable for the current by soldering a small copper wire with a diameter of 0.5-1 mm to its ends, which will act as a leg.
In the power supply circuit, after the fuse, a network filter is installed, built on a high-frequency pulse transformer, a diode bridge and electrolytic capacitors.
I would like to immediately warn you, dear readers, that if you disassemble your power supply and there are no network filter elements there, it means that you have installed a cheap and low-quality power supply in your PC and it will look something like this.
Also, transistors are installed on radiators in the power circuit of the power supply, usually there are only two of them. After which there is a circuit for generating voltage and stabilizing it.
After disassembling, carry out an external inspection of the power supply; there should be no swollen capacitors, burnt radio elements, torn or unsoldered wires, poor soldering, broken tracks on the printed circuit board and other damage, as well as missing radio elements.
The most common cause of power supply failure is simple overheating. This may be due to dust that accumulates inside or a malfunction of the cooling system. Therefore, promptly clean both the power supply and the entire computer from dust, and also periodically lubricate the cooling fans.
Replacing electrolytic capacitors
Swollen electrolytic capacitors are very easy to detect; they have a bulge at the top. Electrolyte often leaks from them, as evidenced by a characteristic drip on the printed circuit board. Such capacitors must be replaced with ones of similar capacity and supply voltage.
In this case, it is possible to replace capacitors of the same capacity with capacitors of similar capacity, but with a higher operating voltage. The main thing in this case is that the size of the capacitor allows it to be placed on a printed circuit board.
It is also important to observe polarity when replacing electrolytic capacitors. If there are a lot of swollen capacitors, then replacing them will not restore the functionality of the power supply; the reason, most likely, is different.
Also, you should not replace a charred resistor or transistor with new ones; the cause of such malfunctions usually lies in other radio elements or circuit components, so without special skills and instruments it will be problematic to discover the cause on your own. In this case, you have a direct route to the service.
The cause of the malfunction quite often is power circuits - these are transistors installed on radiators, a filter and capacitors. You can check them using special instruments or using an ohmmeter. But for this they must be desoldered.
The diode bridge (four rectifier diodes or a diode assembly) can also fail; this element can be checked without unsoldering it from the printed circuit board; use an ohmmeter or a multimeter with a diode test function for this (ohmmeter measurement limit is 2000 Ohm). When connecting the device to a diode in one position, it should show resistance (about 500 Ohms), and when connected inversely, the resistance should be maximum (tend to infinity).
Capacitors are also checked with an ohmmeter, when connected there should be no breaks or short circuits. But when checking the filter, the ohmmeter should show minimal resistance. If a faulty element is identified, it should be replaced with a similar one. Domestic analogues should not be used to replace failed radioelements.
If you managed to find the malfunction and successfully eliminate it, then after turning on the power supply, immediately check the level of all output voltages and only after that install it into the computer. If you were unable to repair your power supply yourself, then do not be discouraged; probably, the cause of its malfunction lies in the supply voltage generation circuit or in other components, which will be very difficult to identify on your own and without special devices. Also, such repairs may not be economically feasible.
Bye everyone and see you again.
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Sometimes it happens that after starting the computer in the morning, instead of the usual quiet operation, the user hears very unpleasant sounds that resemble whistling, grinding or squeaking.
In this case, you should listen to the computer and determine where exactly the sound is coming from. As a rule, the culprit is not the system speaker itself, but one of the devices located inside the PC. Some believe that the processor beeps, but this is unlikely, because this device is a monolithic piece of silicon that is not capable of making any sounds. Therefore, most often it beeps and the power supply does not turn on. Sometimes other components may be the cause, so you need to carry out independent diagnostics.
First of all, it is recommended to dismantle the side cover of the “system unit” and carefully inspect the processor itself, as well as the cooler located on it. After this, you need to try to turn on the computer and carefully move your ear to the expected place where the sound appears.
Most often the hard drive unit or mother card beeps. More precisely, the sounds are made not by them themselves, but by the cooling fans.
Based on the experience of specialists, we can say with 90% confidence that the cause of this trouble is the power supply. In this case, you need to pull it out and try to install another working device in its place. However, this procedure must be performed with care.
Not everyone knows that in the process of replacing a power supply it is necessary to determine the power with which it operates. It is also recommended to check with the manufacturer of this device. If the old power supply squeaks and operates at 300-350 Watts, then the new equipment must meet these requirements. If you install a unit that will have more power, it will not be worse. The indicators should not be lower.
If we talk about the manufacturer, today there are a huge number of Chinese products on sale, which indicate a power of 400-450 watts. However, in reality, such power supplies produce a maximum of 300 Watts, which negatively affects the operation of the power supply. As a rule, when such units are installed, they fail within 6 months of operation.
Having decided on a new power supply and purchased it from the store, you need to get rid of the old hardware. Before starting work, be sure to disconnect the computer and the cable that comes from the power supply. To do this, you will need to remove the side cover of the system unit.
After this, all the wires that come from the old power supply, as well as from other computer devices and the motherboard are disconnected. It is worth paying attention to the fact that additional wiring may come from the video card, if one is installed. At this stage of work, it is recommended to write down which wire was connected where. This will be useful if the user uses a large number of devices.
Then you need to unscrew the 4 bolts that directly hold the power supply itself, located on the back of the computer. After this, the device can be pulled out.
This procedure also does not require any special knowledge. In some situations, for example, when a switching power supply beeps, this method becomes the only solution to the problem.
In order to install a new power supply, you must first screw it to the back wall of the computer. After this, using the previously prepared circuit, you need to connect all the computer devices to the appropriate connectors. At the final stage, all that remains is to close the side cover of the system unit, connect the power cables and turn on the computer.
This will most effectively solve the problem if your computer beeps. If there is no desire or opportunity to completely change the device, then in this case it is necessary to consider other components that may contain problems that cause similar sound signals.
If the power supply beeps under load, this indicates that the problem is most likely in the fan. Since the power supplies of modern laptop computers get very hot, almost all of them are equipped with very powerful coolers. In expensive models, silent fans are installed, which have a longer service life. However, simple power supplies usually have coolers, which quickly fail. This is precisely what explains why the power supply beeps.
Most often, fans start to hum due to dust accumulation. This is explained by the fact that during the cooling process, the blades of the product capture air and, accordingly, accumulate a lot of dirt. In this case, you can try to disassemble the cooler yourself, lubricate it and clean it from dirt.
However, you should not neglect such sound effects. If the power supply beeps because of the fan, then the cooler may fail. This leads to serious overheating and damage to all computer systems. Therefore, in this case, the part must be removed and tried to be restored on your own.
As in previous operations, you must first turn off the computer. After this, the power supply is removed (how to do this was described above). During the work process, you should not rush, since depending on the model of the system unit, the power supply unit can be located both in the upper and lower parts of the unit. In some cases, it is quite difficult to remove it from the system unit due to additionally installed boards.
Before disassembling the power supply, it is recommended to take a photo of it so as not to get confused later in connecting the wires. At the next stage, you need to unscrew the screws located on the power supply cover (usually there are also 4 of them, but there may be 6). After opening the lid you can see the cooler itself. If the power supply beeps, replacing it usually helps.
There is no need to rush at this stage of work. You may not have to buy a new fan.
First of all, you need to carefully clean all the insides of the power supply. To do this, you can use a lint brush, a can of compressed air, or a regular vacuum cleaner.
The most attention should be paid to the fan itself, as a lot of dust accumulates on it. If such manipulations do not help and the power supply continues to beep, then in this case you need to go further.
You need to remove the branded sticker from the cooler and remove the rubber plug located on the bearing. It is not necessary to remove the lock washer; there is also no need to remove the remains of the previous lubricant. It is enough just to drop a little expensive machine oil inside and wait 2-3 minutes until it reaches the bearing. After this, you can install the rubber plug in its rightful place and glue the sticker back on.
During operation, you need to be careful and determine the type of fan. Devices of this class are either removable or non-removable. In the first case, the bearing can be removed without problems and then replaced with a new one. If the power supply is equipped with a non-removable bearing, then in this case all the fan wires will be soldered directly into the board of the device itself. All that remains is to carefully cut the wiring as close to the cooler as possible and clean them. After this, the purchased cooler is installed in its rightful place, and new wires are connected by twisting.
As a rule, such devices operate without fans, but even then they can make an unpleasant sound, especially if the wire winding vibrates inside. In this case, fairly simple manipulations are performed.
First of all, you need to open the case. This is complicated by the fact that most models are glued together. In this case, it is necessary to cut the plastic very carefully with a knife or scalpel. The next step is to coat the coil with varnish. As a rule, 3 or 4 elements need to be processed. However, it is worth considering that the largest coils, which are located very close to the AC source, are usually responsible for the noise. Then just glue the body and wait for the varnish to dry. The same method of solving the problem is used if the power supply of the LED strip beeps.
This element can also become clogged with dust and make characteristic whistling sounds. In this case, the cooler also needs to be cleaned. However, everything is complicated by the fact that these elements operate at a variable speed, which depends on how hot the PC's central processor is. As a rule, the thermal paste in such products dries out, so they fail.
Cleaning and lubricating this fan is much more difficult, so many people prefer to simply adjust the operation of the device using third-party utilities that are installed on the computer. However, you need to understand that this solution is temporary.
If the power supply beeps without load, for example, if you connect it to the network after first removing it from the computer, then in this case you will have to carry out more detailed diagnostics. To do this, you need to use specialized measuring instruments and use them to test all components of the equipment.
It is also worth noting that powerful video cards are always equipped with their own cooling systems. In this case, you need to remove the entire board and its fan. The thermal paste will definitely need to be replaced.
If the laptop power supply beeps, then self-repair will be problematic. In addition, the situation becomes more complicated if the manufacturer of the unit is ASUS. The fact is that in such laptops the cooler and power supply are located in the most inconvenient way. Typically, to get to the fan, you need to disassemble the entire device and remove the motherboard. However, even if these operations are successfully completed, the cooler will have a protective seal. If you remove it, it will be very difficult to install the device back.
On other models, the power supply can usually be removed very easily. To do this, you need to unscrew several screws on the back of the laptop. In this case, you do not have to disassemble the entire unit. Therefore, before work, it is worth considering in detail the design of a particular machine.
First of all, it is not recommended to diagnose problems with the PC turned on. Before removing the cover of the device, you need to not only turn it off, but also unplug the wire from the outlet. Only after making sure that there is no power supplied to the unit can you start working.
When removing any board, do not jerk it sharply. It must be remembered that these elements, as a rule, are additionally attached to the PC case itself with several screws.
When using a vacuum cleaner, do not stick it deep into the system unit. This can damage the circuits. In addition, it is not recommended to use hard or sharp objects for cleaning. In any computer store you can find cans of compressed air that are best suited for such events. You can also use cotton swabs or soft brushes.
When cleaning the cooler and other parts of the power supply, you can use a small amount of alcohol. But you shouldn’t pour it directly into the device. It is enough to moisten a cotton swab in 2-3 drops of hot liquid, and then the old thermal paste will be easier to remove. However, if the PC has not been used for a long time, it will dry to the state of cement and the material will be very difficult to wash away. In this case, you can use specialized tools, which are also sold in a computer store.
An unpleasant beeping sound in a computer can be caused by a variety of problems. However, most often the cause is the cooling system of the power supply. And yet, it is recommended to fix breakdowns yourself only if the user clearly understands what he is doing. Otherwise, you may accidentally cause more damage and end up paying a larger amount of money for repairs. Therefore, it is better to trust the masters.
