ATX form factor: description, characteristics and features

Computer technology is developing. The shape of the devices, their dimensions and technical characteristics are changing. Today we will consider such a concept as the form factor, and its variety ATX - the most popular and popular.

Form Factor

To go to the topic of the article, you need to understand the basic concept. Form factor is the standardization of IT equipment. With its help you can determine the size of the device, the main technical indicators, the availability of additional parts, their location.

Now, speaking of the form factor, people remember the motherboard. Previously, the term was applicable to phone housings, communication equipment and other PC components.

Considering that form factor is a standardized concept, it is referred to recommendatory parameters. That is, thanks to the index, which denotes a certain form factor, it is possible to designate mandatory and additional parameters. Developers try to take the standard for granted and guide them when creating the appropriate component.

Variety

The ATX form factor is not the only standard for components. But this option was in demand for mass production of PCs. He first saw the world in 1995, and Intel became the manufacturer of this architecture. Previously, there were XT, AT and Baby-AT standards, which since 1983 was introduced by IBM.

The ATX form factor influenced the appearance of modified standards. Began to appear abridged formats, with fewer slots and compact sizes. By 2005, a mobile standard, optimized for processors, was developed.

Office computers also began to equip various components of certain standards. Began to appear boards that were used in complex industries. Such modifications of the standard have become known since 2004. The ATX form factor was reincarnated in SSI CEB, DTX, BTX, etc.

ATX

This form factor has become popular since 1995, but the most widespread since 2001. The standard has become dominant in PC production. It affects not only the size of the board or other component. ATX dictates the standard of the PSU, the PC case, the location of the slots and connectors, the shape and location of the slots, the fastening and the parameters of the PSU.

Intel company for a long time thought about what should be the continuation of the form factor AT. By 1995, the developers introduced a new standard ATX. In addition to this company, other manufacturers, who supplied OEM equipment, thought about changing the outdated standard. After the new standard was picked up by those who supplied motherboards and BPs.

For all time of the existence 12 specifications have been let out. Form factor ATX dimensions are standard: in millimeters - 305 x 244, in inches - 12 x 9.6. Modifications that were released under different names were developed on the basis of ATX, but had differences in the location of ports, overall dimensions, and so on.

So, in 2003, Intel wanted to implement BTX. This new standard more effectively cooled the PC system unit. The developers wanted to slowly remove from the ATX markets, which supported the high heat inside the system unit. But even the danger, like overheating of the whole system, did not help to successfully change the format on BTX.

Most of the manufacturers refused to distribute it, as the reduction in power dissipation showed positive results, and in the future it was still possible to achieve good results when cooling the case and without changing the standard. As a result, by 2011 it became clear that there was no need to replace the ATX form factor.

Main changes

So successful invention in this area is not worth waiting for. The user has undergone drastic changes regarding the previous version of AT. The processor was powered by the motherboard. It is served on duty even when it is off. The motherboard provides the functioning of the control unit and some peripheral devices.

It became possible to replace the fan with a larger one and place it on the bottom of the power unit. The air flow became more powerful and covered more elements in the system unit. Changed the number of revolutions, and accordingly, and noise. Over time, there was a tendency to place the power unit at the bottom of the case.

Food

Change the form factor brought a change in the format of the power connector. It was caused by the fact that in the previous format two similar connectors were connected to unsupported slots, because of what the system crashed. In the process of increasing the power consumption, it was necessary to increase the number of power contacts. Developers started with 20, later they became larger, and additional connectors appeared.

Interface Panel

The interface panel became freer. Earlier there was a keyboard slot, and expansion cards were installed in special holes. Form factor ATX added to the slot for the keyboard space for the communicator. The free space was occupied by a rectangular "slot" of standardized size, where the developers put the necessary slots.

Primary Power Supply

In addition to the fact that there is a motherboard form factor ATX, you can find and BP of this standard. Since the development of the format lasted nine years, during this time the developers tried not only to change the connector, but also to make it compatible with the previous forms.

So, initially a connector with 20 power contacts was used. This option was popular before the appearance of a motherboard with a PCI-Express bus. Then came the connector with 24 contacts. To this option was supported and previous versions, "bonus" 4 contacts could be removed, and the board would work with twenty.

CPU Changes

When the new Pentium 4 and Athlon 64 processors began to appear, the standard had to be revised to version 2.0. So, the motherboard began to require a 12-volt main bus. The power supply, whose ATX form factor was also updated to the second version, was to receive an additional connector. So there was an additional connector for 4 more contacts.

After that, variants with complex contacts began to appear. For example, a 24 + 4 + 6-pin connector was claimed for motherboards that received multiple PCI-E 16x ports. A 24 + 4 + 4-pin actually had an additional 8-pin connector, which consisted of two slots of 4 pins. Thus, it was used for motherboards that had high power consumption.

This solution with the combination of two connectors of 4 contacts was due to not depriving the user to connect the model to older motherboards. So, one connector was unfastened from the other, and we received 24 + 4-pin wire.

Housing

In addition to the motherboard and PSU, the corpus also has a certain standardization. ATX form factor in this case is the most modern and suitable for motherboards of the same format. Such a housing assumes an easier access to the entire internal periphery. Has excellent ventilation inside. Allows you to install more than one full-size board.

Despite the same name, the ATX case can be equipped with a micro-ATX motherboard. Briefly about this standard, we'll talk further.

Compact version

The form factor micro-ATX appeared a little later than the basic standard - in 1997. The motherboard of this format is 244 x 244 mm. The variant was developed for processors with an already outdated x86 architecture.

In the process of creation, it was decided to preserve electrical and mechanical compatibility with the previous standard. As a result, the main difference is the size of the boards, the number of slots and integrated peripherals. Micro-ATX is released on the market with an integrated video card, thereby indicating the intended purpose of this standard. PCs with such form factor are suitable for office work and are not designed for gaming projects, since the integrated graphics card is mediocre.

Other options

In addition to ATX and micro-ATX, there was a form factor mini-ATX, which now can not be found anywhere else. Its dimensions are 284 x 208 mm. There was also FlexATX, which measured 244 x 190 mm. This modification is flexible and allows the manufacturer to solve many problems independently.

So, he can choose the size and location of the PSU. Participate in changes related to new processor technologies. But this option could not "fight" with ATX and remains in the background.