A, chassis type
There are many types of chassis. The more common are AT, ATX, Micro ATX three. AT chassis should be the full name of the BaBy AT, mainly used to support the installation of AT motherboards can only be installed in the early machine. ATX chassis is currently the most common chassis, support for the majority of the types of motherboards. micro ATX chassis is based on the establishment of ATX chassis, in order to further save desktop space, and therefore more than the ATX chassis, the ATX chassis. and are thus smaller than ATX chassis. Each type of chassis can only be installed in the type of motherboard it supports, generally can not be mixed, and the power supply is also different. So you must pay attention when shopping. There is also a type of NLX chassis, which is not necessary to introduce because it is not easy to encounter. In addition, there are slim, half-height, 3/4-height, full-height and vertical and horizontal chassis. 3/4-height and full-height chassis have three or more 5.25-inch drive bays and two 3.5-inch floppy drive bays. Ultra-thin chassis are mainly AT chassis with only one 3.5-inch floppy drive bay and two 5.25-inch drive bays. Half-height chassis are mainly Micro ATX chassis which have 2-3 5.25″ drive bays. When choosing, it is best to take the standard vertical ATX chassis as the basis, because it has a lot of space, more mounting slots, good expandability, and good ventilation, which is fully adaptable to the needs of most users.
Two, box material
1, galvanized steel
Chassis box material is an important condition for the selection of chassis. Most of the current chassis box using galvanized steel, the advantages of this steel is better corrosion resistance. As you know, steel exposed to more humid air is prone to corrosion, and galvanized steel can rely on the air to form a dense oxide protective layer of zinc metal to protect the internal steel structure. In the case of being scratched, the relatively active galvanized part can be used as a sacrificial anode to delay the rusting of steel, galvanized layer relatively thicker steel plate corrosion resistance is stronger.
2, painted steel
A few manufacturers of products used only painted rust paint or even ordinary paint steel, so the best chassis do not buy.
3, magnesium-aluminum alloy
For the magnesium-aluminum alloy chassis facing audiophile players, because the surface is protected by a dense layer of oxidation, there is no need to consider the problem of corrosion.
Compared to observing the workmanship, it may be more difficult for the average consumer to judge the strengths and weaknesses of the materials used. An easy way to do this is to dismantle the chassis, observe the internal structure and the thickness of the steel used in the side panels with the naked eye, or lift the chassis to estimate its weight. However, this method is not entirely effective, using high-strength steel, structurally designed chassis can ensure sufficient strength on the basis of minimizing the weight of the chassis, after all, too heavy iron bumps in both the use of maintenance are not convenient.
Generally speaking, the more famous chassis manufacturers produce raw materials import channels and quality control is very strict, exquisite workmanship, solid materials, but the workmanship and materials and costs are closely related to these brand-name products, most of which are priced at a high price. But even so, in the case of funds allow, should also try to choose the products of large manufacturers.
Three, the front panel
In addition to the box, the front panel of the material is also very important. Most of the front panel is made of engineering plastics, the composition includes resin matrix, white filler (common cream front panel), pigment or other color filler (with other colors of the front panel), plasticizers, anti-aging agents, etc., with good front panel strength, toughness, the use of a few years will not be aging yellow; and poor-quality front panel strength is very low, easy to damage, the use of a period of time will turn yellow.
Another point to note is that the front panel modeling is more complex chassis, such as cartoon modeling chassis, due to the panel mold processing difficulties, which will result in an increase in cost, so we recommend that consumers, cheap cartoon chassis as far as possible not to buy, because it can not guarantee that the workmanship of the chassis and the materials used are good enough.
Four, chassis structure
1, the basic structure
A good chassis should have a reasonable structure, including enough expandable slots, can allow users to easily install and remove the accessories of the design, as well as reasonable cooling structure. If a chassis is only good at what it does, but not good at what it does, then it's not going to be a successful product.
As a result of the constant price reductions of various accessories and hardware manufacturers continue to introduce more innovative features of the product, many of my friends have a variety of devices, which makes the 5-inch devices and 3-inch device slots increasingly tense, so consumers should be purchased according to their own needs to fully consider the choice of chassis with sufficient upgradability. For example, consumers need to use a variety of storage devices need to consider in addition to the installation of optical drives and floppy drives, there are not enough slots to install DVD drives, burners, MO drives, ready to buy SoundBlaster Audigy Platinum and other high-grade sound card enthusiasts need to be arranged for the location of the external control box, and like to play with the friends of the RAID will have to look at! Whether there are enough slots to install their own multiple hard disk. Currently popular slot arrangement is no less than four 5-inch slots, 1 to 2 3-inch drive bay and more than two 3-inch half-height hard disk slots (3-inch slots totaling at least 4), less than the number of slots in the chassis for hardware enthusiasts now have to carefully consider whether to buy. For the average home user with no special requirements, the requirements can be relaxed, and if you don't have to think about adding equipment in the future at all, then you can pick from a wider range of candidates.
2, disassembly design
For hardware enthusiasts who often open the chassis, easy disassembly design is even more essential. Currently in many chassis have this design, such as side panels with hand screws fixed, 3-inch drive racks with card hooks fixed, 5-inch drive with screw-free shrapnel, boards with screw-free fixation, the front panel of the chassis with the addition of USB ports and so on. However, it is important to note that while some designs bring convenience to the user, they may also negatively impact the overall structural strength of the chassis, which consumers should consider when purchasing.
3, thermal design
Reasonable thermal structure is related to the computer can work stably important factors. High temperature is the killer of electronic products, too high temperature will lead to system instability, accelerate the aging of parts. With the continuous increase in CPU frequency, the widespread use of high-speed hard disk, high-performance graphics cards frequently updated, the chassis internal cooling problem is also more and more attention. Currently the most effective chassis cooling solution is used for most of the chassis dual-program interactive cooling channel: external low-temperature air from the front of the chassis intake cooling fan into the chassis, through the Southbridge chip, a variety of boards, the Northbridge chip, and finally reached the CPU near the CPU cooler, after the CPU cooler, a portion of the air from the back of the chassis exhaust fan pumped out of the chassis, and the other part of the power supply bottom or rear Another part of the air from the bottom or back of the power supply into the power supply, power supply cooling, and then by the power supply fan out of the chassis. The chassis fan uses more than 80mm specifications of large air volume, low speed fan, to avoid excessive noise, to achieve the "green" cooling.
In order to more smoothly on the high-speed hard disk cooling, some manufacturers use in the three-inch drive frame in front of the installation of additional air intake fan method, not only to increase the chassis air flow, but also can be directly on the hard disk cooling. Another novel solution idea is to move down the traditional hard disk mounting position, so that the hard disk and the bottom of the chassis contact, this method both the use of the chassis floor to enhance the hard disk heat dissipation, but also to make the fresh low-temperature air into the chassis to the hard disk heat dissipation first, significantly reducing the hard disk heat, extending the service life of the hard disk. There are also manufacturers in order to avoid the chassis messy cable affect the flow of air, set up in the appropriate location of the cable clamp, you can fix the data cable and power cord in a position that does not affect the air ducts. These designs should be prioritized when purchasing a chassis.
A well-designed dual-programmed interactive cooling channel ensures that 90% of the heat inside the chassis is distributed in a timely manner, but some chassis manufacturers have added fans on the sides and top of the chassis to "improve" the dual-programmed interactive cooling channel, which makes the air flow inside the chassis change: the air from outside the chassis enters the chassis, and the fan on the top of the chassis forces convection. After the air from outside the chassis enters the chassis, due to the fan on the top of the chassis to force convection, part of the fresh air does not follow the original route to reach the vicinity of the CPU, and is pumped directly out of the chassis, instead of wasting some of the low-temperature air cooling effect. In addition, the plastic side panels used by some manufacturers will also have a negative impact on the heat dissipation of the chassis: because the plastic is a poor conductor of heat, it will prevent the heat from being discharged from the chassis through conduction and radiation. In addition, some chassis on the market in order to make full use of the space inside the chassis, the installation of various devices crowded, and even the power supply will be placed directly above the CPU cooling fan, these designs will seriously affect the heat dissipation, unless the user has a special need to buy.
Five, conductivity
Whether the chassis material is conductive, is related to the chassis inside the computer accessories is a very important factor in the safety. If the purchase of the chassis material is not conductive, then the static electricity generated by the chassis chassis can not lead to the ground, serious cases will lead to the chassis inside the motherboard burned out. Now chassis materials are generally steel plate, and steel plate is divided into two kinds, the first, is the use of cold galvanized electrolytic plate, this chassis conductivity is good; the second, is only coated with antirust paint or even ordinary paint steel plate, conductivity is poor. The appearance of the chassis color is so similar today, how to distinguish it? In fact, it is very simple, just put the meter that the stylus is placed on both sides of the chassis plate, if the stylus in the meter does not move the needle, it shows that this chassis is not conductive, is painted directly on the steel plate.
Six, electromagnetic shielding performance
Our computer at work will produce a lot of electromagnetic radiation, if not prevented will cause some harm to the human body. Many consumers have noticed the harm of radiation, in the purchase of computers specified by TCO'99 certified monitor. But most people ignore the electromagnetic radiation generated by other accessories, these radiations mainly from the motherboard, CPU and graphics cards, sound cards and other equipment. This chassis has become the shielding of electromagnetic radiation, to protect the user's health of the last line of defense. In addition, a well-shielded chassis can also effectively block external radiation interference, to ensure that the computer is not affected by external radiation. So, how to buy a well-shielded chassis?
1, open hole in line with the norms.
In order to increase the cooling effect, the necessary parts of the chassis will be open holes, including the side panel holes, exhaust fan air intake holes and exhaust exhaust holes, etc., but the shape and perimeter of the hole must meet the requirements. Electromagnetic waves inside the chassis will be generated into the surface of the chassis inductance current, when the current through the hole, it will be radiated in the form of emission of energy, the size of this radiant energy and the perimeter of the hole. In order to shield the electromagnetic wave generated by high frequency equipment, the perimeter of the hole should be at least less than 1/20 of the wavelength, the same area of the hole, the perimeter of the circular hole is the smallest. So the openings on the chassis should be as small as possible, and should try to use round holes.
2, a variety of lights and switches wiring electromagnetic shielding
Secondly, we should pay attention to a variety of lights and switches wiring electromagnetic shielding. Longer connection lines need to be designed into a stranded line, or add a magnetic ring on the line to reduce electromagnetic radiation leakage.
3, the details of the shielding design
The last thing to pay attention to is the details of the shielding design. For example, in the chassis side panel mounting, rear power position set radiation shrapnel, this shrapnel will make the connection between the equipment more closely, effectively preventing radiation leakage. Some manufacturers produce chassis 5-inch and 3.5-inch slot baffle are used with anti-radiation shrapnel and anti-radiation slot steel, more effective shielding of electromagnetic radiation, but many chassis electromagnetic radiation shielding design tends to ignore here, just use the ordinary steel as a baffle.
A more intuitive way for consumers to determine whether a chassis has good radiation shielding is to look at whether the chassis has passed the EMI GB9245 Level B, FCC Level B, and IEMC Level B standard certification, these civilian standards provide a safe limit of radiation, and these certified chassis generally have a detailed certificate of proof.
The above points are what you should pay attention to when buying a chassis. After meeting these requirements, the beautiful appearance is the next factor that should be taken into account. Choosing a chassis with a beautiful style, excellent materials, reasonable structure, and safe use is our ultimate goal
This is the first time we've chosen a chassis with a beautiful style, excellent materials, reasonable structure, and safe use.