Hello!
How to choose the chassis?
In the process of saving the machine, perhaps the most easily overlooked part is the chassis. Most DIY installers will carefully analyze CPU, graphics card, motherboard and other components to find out the best cost-effective configuration or the "cool" configuration that suits them best, but they often ignore those things with low value content and think that these are "what you have", and the chassis is a component in this "forgotten corner". We only pay attention to the appearance of the chassis at most, and don't care about the brand and model, let alone the materials and workmanship. So we will see that when configuring the machine, we usually find that there is not much money left after buying all the accessories, so we choose a better power supply and the chassis can only make do with the cheapest one. At most, if you see the look you like very much, you will be determined to buy a good-looking one. Anyway, everyone thinks that the chassis is just a device with fixed accessories. As long as it looks ok, any chassis can be used, and the quality of various brands is not much different.
Actually, this is a misunderstanding. As the "home" of computer accessories, the chassis should be paid more attention to by DIY, not only because its quality is related to the convenience of computer disassembly, but also to the position coordination among the accessories. Below, I will give you a few wrong examples as a warning:
1) thinks that the chassis is just like an electronic product, the lighter and thinner the better.
Hehe, the case is still the product of "heavy industry". At that time, the product evaluation standard of electronic industry was not applicable to this case. Why do you say that? After all, the chassis is not the kind of thing that can't be repaired once it is put away. You still have to move once in a while. If it is light and thin, can it stand up? Bian Xiao has seen an example of this. A friend moved the computer to another place, and XP died there before entering the system when it was turned on. At first, I thought it was a software problem, but later I reinstalled it and used a floppy disk to kill virus. It's really bad that it still exists after a day's trouble Pull me over, and I'll take the case apart, and the contents will be divided into eight pieces, and then I'll pack them one by one. As a result, the problem appeared. Hehe, many people must think it's an accessory problem. Either this one is broken or that one is burned, because everyone knows that XP requires high hardware, and everyone knows this bad performance and characteristics. But the problem actually lies in the chassis, because my friend randomly asked for a chassis when he bought a computer. As a result, JS gave him a very thin computer. As a result, when moving, the back of the chassis was deformed and the graphics card was squeezed out of the AGP slot a little. As a result, poor contact made it impossible to access XP system. Hehe, after this time, my friends are careful every time they move the chassis. Well, I knew it, so why bother? ^_^。
So how do you look at the border of a chassis? Generally speaking, the outside of the cabinet is usually composed of a layer of steel plate with a thickness of 1mm or more. The thickness and material of steel plate are directly related to the rigidity of the box, as well as the ability of sound insulation and electromagnetic radiation prevention. The thickness of the steel plate used in the case produced by regular manufacturers is not less than 1.3mm, but the thickness of the steel plate used by some small manufacturers is only about 1mm, so you don't need to use that ruler to measure it. As long as you put it on, the heavier the chassis, the better. In addition, you can play the shell of the chassis with your fingers. If you can hear the ringing knock, it proves that the steel plate of the cabinet is thin and brittle. If you hear a dull and heavy sound, then the material of this cabinet must be good. A good steel plate is generally coated with a thin layer of zinc (bright part). In this case, it can withstand high strength, impact resistance, high hardness and strong elasticity. The steel used in the chassis frame is generally made of high-quality materials with high hardness and folded into angle steel shapes or strips. We can shake the chassis frame with the shell removed by hand. A good chassis should be relatively stable, and an inferior chassis is easy to shake when it is light. When choosing, we should also pay attention to whether the trimming of the outer layer and the inner bracket of the chassis is smooth, and a good chassis will not have burrs, sharp edges and burrs. If the inferior chassis appears the above phenomenon, "blood spatter" will often occur during installation. Generally speaking, the chassis should be grinded before leaving the factory. Smooth the edges of some steel plates and round the corners, which will fold some corners accordingly. When installing such a shell, you won't worry about being cut. Some inferior shells with rough workmanship are often easy to scratch your hands.
2) Pay too much attention to appearance, but ignore heat dissipation and positioning.
This problem is often more prominent in MM. With the improvement of people's taste, many manufacturers have introduced personalized chassis to meet those users who have higher requirements on appearance. Indeed, the computer is still very eye-catching at home. Besides its function, it should be a good appreciation. There are many designs on the market now, such as bright colors, novel shapes, transparent shells and so on. These have greatly attracted the attention of consumers. However, often behind these shapes, there are hidden dangers of heat dissipation and fitting positioning.
Now many manufacturers have introduced small and exquisite protective covers, and some have also introduced many mini-protective covers in one machine style. As a result, many mm's who love beauty flocked to the shopping list, and many gg's who follow the fashion also joined the shopping list. If it is the design of a famous factory, many heat dissipation problems can be improved by internal air duct design. But if it's some inferior imitations, it will bring more heat dissipation and parts positioning problems at the same time. Reasonable chassis structure design, while considering the appearance, we must pay attention to the chassis air duct design, that is, in the case of natural windless, where the air intake is the most appropriate, where the air intake effect is the best, and where the air exhaust is the smoothest (so that the heat energy will not stay inside and the chassis can be quickly eliminated). At the same time, we should also consider the size and position of air holes, whether the position design of inlet and outlet fans forms effective convection, etc. This is the most basic requirement of air duct design. However, many "small" inferior cabinets often do not consider the design of the air duct when imitating the appearance. This will often lead to poor ventilation, heat can not be discharged from the cabinet, forming a heat island in the cabinet. In this case, the system will be unstable, the life of accessories will be shortened, and accessories will be burned because of overheating. At present, the heat of cpu and graphics card is very "horrible". I hope that friends with powerful cpu graphics cards will pay special attention to this problem and don't lose too much because the chassis is "small". While paying attention to heat dissipation, the accessories in the most basic standard of a good chassis should be positioned reasonably, and many different types of motherboards (such as ATX and micro ATX) can be installed. At the same time, the position of the card should be properly positioned, and the card cannot be installed because of the card dislocation. A friend bought a motherboard with five pci slots, plugged in a network card, a sound card and a TV card. As a result, when he wanted to play SCIS, when he happily inserted the SCIS card, he found that there was no place to insert the card, dizzy! The card slot on the motherboard and the card slot on the chassis can't match, because the five card slots on the chassis can't match. In the past, there was no "expansion space" by barely using three. So friends who like to play different games should not only look at how many PCI slots there are on your motherboard, but also look at whether your chassis can have such a suitable card slot.
3) the place that is easily overlooked-anti-static.
Whether it is the material selection, workmanship, layout or structure of the chassis, these can be seen at the time of purchase. What can't be seen or easily overlooked when buying? That's antistatic. Because many times, when the computer is turned on for a period of time, static electricity has accumulated, which will make you fly. DIY people generally like to play with computers, but when disassembling computers, they often encounter cases with poor anti-static performance. When their hands touch the back panel of the chassis (except that the back panel of the chassis is exposed, the other parts of the chassis are painted, and basically no static electricity is felt), it will be very painful to go to electricity, so they can only move the chassis after unplugging the electrical plug for a while. If it is serious, you must discharge the chassis to completely eliminate static electricity. A friend, who stayed up all night, bought a pair of headphones in order not to affect his family. As a result, he got an electric shock as soon as he put it on. After that, the headphones stopped listening. Tell me how painful it will be if this happens. In addition to being harmful to human body, it is also a big killer to the accessories inside the chassis. General static accumulation will interfere with the communication of the board, leading to system instability or endless restart, and a large amount of static accumulation will cause irreparable damage to the board. Static electricity is one of natural enemies of all electronic components. A small amount of static electricity is enough to break down some fragile electronic components, leading to the failure of the whole set of electronic equipment, and many circuit boards have directly exposed parts, which provides conditions for electrostatic crime. Therefore, it is very important to choose a good anti-static chassis when installing the machine. Generally speaking, galvanized sheet has a good antistatic effect. In fact, when the computer works normally, the monitor and the host will generate static electricity, which needs to be conducted away. But now many household wiring is not standardized and the ground wire is not well grounded. After our test, some zero lines are connected to the ground wire, and some ground wires are still charged, which can't lead away static electricity. If the human body forms a path with the ground, such as touching the computer shell without shoes, it will feel numb. Improve wiring. If it is difficult to do so, connect one end of wires, such as iron wire, to the chassis, and the other end to a place that can be well grounded, such as window sill metal buckle and water pipe, and keep good contact at the joint (both ends are connected to bare metal, not to places with insulating materials such as paint).
How to choose power supply?
Now the information is more and more developed, and IT is also because of the vigorous promotion of IT websites and IT magazines. I believe many friends have studied PC hardware. When configuring the machine, we often choose PC accessories such as motherboard, graphics card, memory, sound card and hard disk, but I am afraid that most friends will not choose power supply themselves. This important link is often completed by the merchants in the last column of the distribution list. At best, you just focus on motivation or brand. Of course, because the chassis and power supply are often integrated in the installation process, the purchase of power supply has become an easily overlooked part when you choose a computer. The average consumer, because he doesn't understand, is easy to listen to the advice of the merchants, and if he is unlucky, he will buy inferior power supplies.
With the development of science and technology, today's computers have more and more powerful functions, more and more accessories and more complex structures. Many of these accessories are big power consumers, such as hard disk, CD-ROM drive (especially burner), graphics card, CPU and so on. In addition, there are all kinds of PCI sound cards, built-in modems, and chassis fans, CPU fans, graphics fans and so on. Just as the heart is to the human body, power supply is the source of power, and its importance cannot be ignored. If the computer often crashes or restarts inexplicably, a big possibility is that there are too many devices in the host, and the power supply cannot provide enough and stable energy for these devices, resulting in insufficient voltage and paralysis during operation; Not only that, inferior power supply will also cause the burning of components and accessories, and more seriously it may threaten the health and life safety of users. Therefore, the quality of power supply directly affects the service life of the computer. So, what is a quality power supply? Bian Xiao believes that to become a high-quality power supply, three basic conditions must be met:
1) passed the national professional certification.
Power certification is a professional standard for power supply formulated by certification bodies according to technical specifications in the industry, including production technology, electromagnetic interference, safety protection and so on. Usually, products that meet certain indicators can only use certification marks on the packaging and product surface after passing certification to prove their quality and reliability.
Common certifications include 3C certification, UL certification, FCC certification, CE certification, CSA certification, CSA certification and CCEE certification. Among them, 3C certification ("China Compulsory Certificate", Chinese name is "China National Compulsory Product Certification") was implemented on May 1 this year, which is the abbreviation of China National Compulsory Product Certification. It integrates CCEE (Great Wall Certification), CCIB (China Import Electronic Product Safety Certification) and EMC (Electromagnetic Compatibility Certification), and it is superior in many indicators such as electromagnetic radiation. CCC certified power supply should have CCC certification mark on the power supply label. Non-CCC certified power supply has no CCC mark. In the internal circuit, CCC power supply generally has PFC circuit, which is more efficient in the use of electric energy and less polluting to the power grid. CCC power supply with source PFC circuit has stable output and wide adaptive voltage, but non-CCC power supply generally does not. The evaluation index of PFC (Harmonic Current Limiting) circuit is specially formulated for the problem of harmonic current. Due to the development of internal converter technology of power supply, people's utilization efficiency of electric energy has been greatly improved, but the use of a large number of switching power supplies and thyristors has also led to the generation of harmonic current. Harmonic current is very harmful. On the one hand, it increases the burden on the center line of the power grid, and a large number of harmonic currents generated by nonlinear loads will flow through the center line, causing the center line to be overloaded. In severe cases, it will burn out the central line and cause a fire. On the other hand, it increases the burden of high-voltage capacitor of power grid. High-voltage capacitor is usually connected to the power grid transformer to filter out the high-frequency interference of the power grid. The high-frequency harmonic current flowing through the capacitor will raise the temperature and even explode. In addition, harmonic current will also cause voltage waveform distortion of power grid, thus affecting the stable operation of other electrical products. Moreover, PFC can not only completely control the voltage fluctuation between 180 V and 265 V, but also protect and control the voltage stability. It can also avoid all kinds of computer failures caused by unstable current, completely avoid the harm caused by harmonic current, and effectively improve the purity of public power grid, thus greatly improving the safety performance of power supply and effectively ensuring the interests of users. Power products listed after May 1 must pass 3C certification. Therefore, 3C certification has become an important indicator for us to purchase electricity.
2) The power supply is heavy enough.
Generally speaking, a good power supply is not too light. When buying a power supply, you can estimate it in your hand first. Basically, the heavier the better. For example, the original power supplies of IBM and Dell are very heavy. Why? There is a reason for this. First of all, the power supply shell, a good shell, is generally made of high-quality steel. There are two standard thicknesses of power supply housing: 0.8mm and 0.6mm, and the materials used are also different. Here, Bian Xiao teaches you a very discriminating method. Draw a few times on the steel plate with your nails. If there are scratches, it means that the steel quality is poor. If there is no trace, it means that the steel quality is good. At the same time, the weight directly indicates the quality of the material. Generally, the heavier the power supply material, the better. Followed by the internal parts of the power supply, such as transformers, heat sinks and so on. It's also heavier and better. Why do you say that? Such as transformer, is an indispensable part of power supply. It mainly converts DC voltage into high frequency AC voltage. The simple way to judge is to look at the size of the transformer. Generally, the inner diameter of transformer coil for 250W power supply should not be less than 28mm, and that for 300W power supply should not be less than 33mm, so the bigger and heavier the better. Heat sink, because the power tube inside the power supply is a large heating body, its high heat will have a great impact on the normal work of itself and surrounding components, so a large heat sink is installed on the power tube. A good heat sink for power supply should be made of aluminum or even copper. The larger the volume, the better the heat dissipation effect. Generally, heat sinks are made into comb shapes. The deeper the teeth, the wider the teeth and the greater the thickness, and the better the heat dissipation effect. Basically, it is difficult for us to see the heat sink clearly without disassembling the power supply, so the intuitive way is to judge by the weight. In addition, a good power supply will generally add some components to improve the safety factor, so the weight will naturally increase, while a poor power supply will save some capacitors and coils and the weight will be lighter.
3) Good heat dissipation
In addition to using radiator to dissipate heat, in fact, the heat dissipation of power supply mainly depends on special fans, so the quality of fans often has a direct impact on power supply. You may not have noticed that in the process of power supply, the loose piece only radiates heat into the air. If the hot air cannot be discharged in time, the heat dissipation effect will be greatly reduced. The arrangement of fans plays a decisive role in heat dissipation. At present, there are mainly single fan and double fan designs, which can speed up the airflow and increase the noise accordingly. Single fan design has low noise, but the heat dissipation effect is not as good as that of double fans. The air flow rate driven by the fan per unit time is directly related to the heat dissipation effect. The problem of general flow is simply the speed of the fan, and then it becomes power and current. Generally speaking, rated current has become an important indicator of purchase. Under the same voltage, the greater the current, the higher the fan power and the greater the wind power, which is also a major standard for us to choose. Take the 8 cm 12V DC fan used in general power supply as an example, and its rated current is generally between 0.12 and 0.18a ... In addition, the design of the air outlet also has a lot of influence on heat dissipation. Generally, the grid bars at the air outlet of power supply are wide, which greatly hinders the flow of air. However, some power supplies use sparse steel mesh, which further reduces the obstruction to air and effectively reduces the probability of dust entering the power supply on the premise of ensuring safety.
With the three main criteria for judging the power supply, we should be confident to buy a satisfactory power supply, but we must avoid several misunderstandings in the process of purchasing.
Myth 1: The greater the power, the better.
Some merchants boast to users that their power supply can reach 350W or even 400W. In fact, if the ordinary multimedia computer is not connected with a monitor, the actual power consumption is less than 200W W, which is more than enough for ordinary users, even if it is equipped with P4,300 W power supply. Therefore, when purchasing power supply, there is no need to deliberately pursue the power of power supply. On the contrary, stability is the most important. As long as it is a qualified commercial power supply, it can meet the needs of most users.
Myth 2: The newer the 2:ATX version, the better.
Some merchants advertise that their power supply conforms to the latest Intel ATX 2.03 standard, which seems to be much superior to others. In fact, from ATX 2.0 1 to ATX 2.03, it is just some harmless modifications for ordinary users. At present, the power supply conforming to ATX 2.0 1 standard can meet the basic household use.
Myth 3: The power quality of the same brand is the same.
Consumers often think that the quality of the same brand power supply of the same manufacturer and the same production line should be roughly the same, but it is not, and the quality difference between different models of the same brand is not small. You can find the difference between different models according to the knowledge introduced above.
Recommend a chassis:
Chassis: Foxconn Xue Fei ATX 140
Model: Foxconn Flying Snow ATX 140 258 Yuan with its own power supply
Configuration: vertical ATX /3*5.25 inch position, 3*3.5 inch position /0.7mm SGCC/ original P4 FTEK-3 18A ATX3C certified power supply/net weight: 6.4KG/ color: blue, gray, silver gray. Very cost-effective chassis.
Foxconn is an internationally renowned computer connector and port manufacturer!