The power supply is as important as the heart of the human body in a P.C., and a suitable power supply product can provide a stable power supply to other hardware in the P.C. host to ensure their regular operation.
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Analysis of the difference between AT and ATX power supplies
AT power supply and ATX power supply are the working power supply of the computer, the function is to convert the A.C. 220V power supply to the D.C. 5V, 12V, 24V power supply used in the machine. As “uninterruptible power supply” is composed of the battery pack, inverter, and control circuit, it can provide continuous power protection and energy storage equipment in the event of grid abnormalities (power outages, surges, Undervoltage, market power subsidence, radiation interference, etc.).
Its inputs and outputs are all 220V A.C. For critical computers; UPS power can be used to keep data secure.
The ATX power supply is widely used in computers, compared with AT power supply, it is more in line with the “green computer” energy-saving standards, it corresponds to the motherboard is ATX motherboard.
There are two main differences between AT power supply and ATX power supply: interface and voltage, ATX power supply pins are 20 pins, of which pin 1 is square, and the rest is round;
What is an AT power supply?
AT power supply is mainly used in the early motherboard (such as AT motherboard and Baby AT motherboard); now, the AT power supply has been eliminated.AT power supply power is generally 150W ~ 220W, a total of four outputs (+5V, -5V, +12V, -12V), another motherboard to provide a P.G. signal.AT power supply volume is 150mm × 140mm × 86mm.
What is an ATX power supply?
Unlike the AT power supply, the ATX power supply has some improvements on the line; the most crucial difference is that the ATX power supply itself does not entirely cut off the power when turned off, but maintains a relatively weak current. At the same time, it uses this current to add a power management function called Stand-By.
It allows the operating system to manage the power supply directly. With this feature, the user can achieve a soft shutdown instantly through the operating system, but also networked power management.
If the computer is turned off, a signal can be sent to the computer through the network. Then the monitoring circuit will send a +5V S.B. activation voltage unique to the ATX power supply to turn on the power to start the computer, thus achieving a remote control on.
The ATX power supply has two main versions; one is ATX1.01 version, the other is the ATX2.01 version. 2.01 and 1.01 version of the ATX power supply, in addition to the location of the cooling fan, is different; their activation current is also different. 1.01 version only 100mA, 2.01 version has 500mA ~ 720mA, which means that 2.01 version of the ATX power supply will not be as “allergic” as 1.01 version, often subject to external voltage fluctuations and start the computer.
What is an SFX power supply?
Intel introduced the Micro-ATX motherboard form factor in December 1997, along with a smaller SFX (Small Form Factor) power supply to accompany it. Since then, SFX power supplies have been widely used in many new compact P.C.s. Currently, the latest version of the SFX specification is SFX12V version 3.0.
The SFX power supply is specially designed for small systems that include a limited amount of hardware. It provides slightly less continuous power and 4-stage voltage (+5V, +12V, -12V, and +3.3V). For small systems, this capacity is sufficient, and SFX power supplies are generally not available at -5V, but this is not a big problem for current motherboards, after all -5V and practical -5V ISA slots have been eliminated.
The SFX main power connector is the same as the ATX, after all the two are compatible, so players don’t need to worry about the motherboard incompatibility after choosing the SFX power supply. However, due to the small number of SFX power supplies and high integration, they are much more expensive than ATX power supplies.
During the development of the P.C. power supply, there have been many standards. Still, eventually, ATX power supply became the absolute mainstream, only a small number of the supermini platform only practical SFX, TFX power supply. As strong as Intel, pushing the BTX power supply also suffered a Waterloo. Thus, in the face of internationalization standards, any departure from them will be discarded.
How to buy a quality power supply?
First observe the outer packaging of power products, what is good packaging? The first is to have better protection of the power supply products, that is, the overall sturdy, to ensure that the product in transit will not be damaged by various bumps.
The second is to have precise product specifications, such as rated power, output specifications, and various certification marks, and this information should be consistent with the power supply nameplate label.
In addition to the outer packaging of the power supply, we also have to see the power supply’s enclosure and cables. The power supply case is our most direct feeling about a product, we do not require a personalized case, but the necessary materials should still be enough.
The inadequate quality power supply in this regard can be said to be able to save, not only the appearance of dull, and the shell material is also fragile, the cable looks at two aspects, one is the number of interfaces provided, the current mainstream power supply in addition to the 24-pin main power supply interface, CPU power supply interface has been upgraded from the standard 4-pin to 4 + 4-pin, PCI-E interface from the standard single 6-pin upgrade to 6 + 2-pin or even dual 6 + 2-pin, SATA interface and D-type 4-pin interface has also been increased in number, more high-end products provide more interfaces.
However, if a power supply that is claimed to be mainstream only provides a small number of ports, not even the 6-pin and 6+2-pin ports used to power the graphics card, then it means that the power supply is either too old and out of the mainstream, or the output power is not enough unless you only need these ports, the platform power is low enough, and will not upgrade the P.C. for a long time to come. Otherwise, this power supply is not recommended.
And in addition to the interface of the power supply, the power cord is also essential. P.C. power supply on the current typical wire specifications to 16AWG, 18AWG, 20AWG, and 22AWG mainly, according to single-core PVC insulated wire in 30 ℃ environments, to heat up to the maximum applicable temperature of PVC material, common 16AWG, 18AWG, 20AWG, and 22AWG wire can pass the current is 24A, 18A, 13A, and 10A, that is, the smaller the wire specifications, the cable can bear the higher the current, the better the quality.
Currently, most mainstream power supplies use 18AWG cables, while most 16AWG wires are only used in flagship products. The 20AWG cable or 22AWG cable is mostly used in low-end products, so we can use 18AWG cable as the dividing line between recommended and not recommended.
Now that a mainstream-grade power supply with a full range of materials can hardly weigh less than 1kg in any case, high-end products will only get more substantial. However, when you get a power supply that apparently weighs less than 1 kilogram and even feels light, it’s a severely shrunken product. At this time, we can choose to look at the power supply fan and heat sink to see if the power supply material is complete. For the weight of the product is too light, most is completely streamlined a level EMI and two EMI circuit, the arrangement of the heat sink is also able to less is less, such a power supply often has greater security risks, indeed can not choose.
How much power is appropriate for a computer power supply?
How much power to buy depends mainly on the sum of the power consumption of all the hardware, with some power space to allow for overclocking or upgrading backup. When we buy each piece of equipment, check the parameters of the hardware model that will be marked with power consumption. Generally, the sum of all the hardware power consumption plus 100W is the power rating you need; if the computer power is not enough, it will cause the computer to restart automatically.