Computer power supply ATX

Actually, ATX is a standard that contains requirements not only and not so much for power supplies, but, first of all, for computer cases and everything that is associated with them, in general.

To begin with, you need to go a little deeper into the story. The first standard form-factor of computers, which received a mass distribution, was the standard AT. It was released in the mid-1980s by IBM as a kind of unified alternative to several different form factors that were then present on the market. The necessity of having one industry standard at that time was already ripe for a long time. And in standardization everything was needed, from the power supply system to the type of attachment of expansion cards and plugs for the rear panel of the input-output ports.

Gradually, the title of locomotive of everything new in the industry from IBM was imperceptibly adopted by Intel. It was she who became the ideological inspirer and the main author of the ATX standard. The power supply in the new standard outwardly underwent insignificant changes, the main innovations concerned the connectors for connecting the motherboard and peripherals, as well as the "stuffing" of the device.

One of the main innovations that was noticeable to any user was that the ATX power supply was able to control the power of the computer. This is turning off the computer, and turning on the schedule, and managing the main currents in order to optimize the power consumption of the computer. The ATX power supply now, besides the power lines used solely for powering the computer components, had a number of signal lines to control the power supply.

The power connector of the motherboard has also changed. Now the connector, through which the ATX power supply supplied voltage to all the key components of the computer, it was simply impossible to stick incorrectly (this error was very common when connecting an AT power supply unit, which cost "life" to many motherboards). In general, as a whole, the form factor ATX is characterized by great reasoning from the point of view of ergonomics and "foolproofness", rather than its predecessor.

During its existence (and this, considering that the first audit was released in 2001, for more than 10 years), the standard has undergone a number of changes, including very significant ones. So, for example, with the advent of Intel Pentium IV processors, there was a need for additional 12-volt power, because The new devices were distinguished by extreme "gluttony". Old ATX power supplies simply could not transmit the required power current through the +12 V line needed to power these chips.

Currently, the ATX power supply has the following main connectors for connecting power to computer components:

• 24-pin power connector to the motherboard. Often 4 contacts are separated on a separate shoe to ensure compatibility with obsolete motherboards. If we consider that almost all the "mothers" issued after 2004 require 24 contacts, the need for such a dismountable connector gradually comes to naught;
• 4-pin (rarely - 8-pin) auxiliary power connector for the processor;
• 4-pin connectors for powering the drive and old IDE devices. These connectors changed from the standard AT without changes and are now used, rather, for compatibility with legacy devices. At one time, with the help of a 4-pin Molex plug, there was sometimes an additional power supply for video cards (the connector was connected directly to the device or via a specially wired connector on the motherboard). Now this anachronism has already sunk into oblivion;
• 5-pin connector for SATA devices;
• 6- or 8-pin connectors for additional power supply for the video card. On the 6-pin connector, it is possible to transmit current up to 75 W, 8-pin to 150 W. Power supplies up to 450-500 W typically have only one such connector. Further, with increasing power of the power supply unit, and as a result, by increasing the maximum possible appetite of computer components, the number of such connectors also grows. In some power supplies, produced in 2004-2006, there was no such connector at all, although they could easily pull out a gluttonous video card with a power of 100-150 W. In this case, there is no problem to find special adapters with 4-pin Molex.

The ATX standard, despite its considerable age, continues to improve actively, adapting itself to the needs of the modern computer industry. ATX power supplies are no exception. The capacities are growing, the equipment manufacturers are putting forward new requirements to the parameters and the quality of power supply for the components of the system unit. In recent years, there have been separate attempts to bring to the market some alternative to ATX. What is the unsuccessful attempt to introduce the form factor BTX (by the way, the brainchild of the same Intel). But so far in every new desktop computer is still the same good old power supply ATX-standard.