Building a computer from scratch requires an exhaustive evaluation of all the components that will lead it to be the best among all. The center of the correct operation of a CPU is the motherboard or motherboard, where all the elements that make up a computer are connected. Since the beginning of this century, technological advances have occurred very quickly compared to the time of the 80's and 90's. So managing to acquire a good motherboard has become quite a challenge, due to the range of existing models and brands. But to reach the point of modernization that we have today, it is necessary to know where all this wonder that we also call motherboard was born and that gives us the possibility of creating or developing a world of ideas on a screen.
What is an AT motherboard?
Advanced Technology (AT) is the motherboard format used by the IBM AT in full desktop and full tower format. There's also the AT power supply, which is a device that fits inside the computer case. It is responsible for transforming alternating current from the power line into direct current. The
AT motherboard was released in 1984 as a replacement for eXtended Technology (XT), with each manufacturer producing PCs differently, making part swaps, hardware upgrades, and other operations impossible. It was the first successful attempt at standardization for base plate shapes. However, over time, new shortcomings were discovered that led to its replacement. Its large size played against it since it was difficult to introduce new drives. An AT motherboard has dimensions around 100 millimeters, so large that it does not fit on a mini desktop. So the concept of six-pin connectors had to be created to function as the power connectors on these types of motherboards. In the days of IBM-compatible personal computers, the AT form factor referred to the
motherboard dimensions and layout for IBM AT. Many third-party manufacturers produced IBM AT form factor-compatible motherboards, just like previous models (IBM PC, IBM XT) did, so users would upgrade their computers with faster processors.
Cloned model
By the 1980s, the
IBM AT model was the most copied by IBM clones which began to use AT-compatible designs, increasing its popularity. As late as the 1990s, AT motherboards and their components were sought after. He
original design measures 13.8 x 12 inches, this means it won't fit in mini desktop racks and takes up space behind the drive bay. So as already mentioned, this prevents new drives from being added. Clone manufacturers also took notice of the power connectors. Those on AT motherboards are almost identical two-pin and six-pin plugs.
IBM designed the mechanically coded connectors so that each one can only be inserted into position correctly. However, some clone makers played to cut costs at this point and used uncoded, ie interchangeable, connectors. Unfortunately, the two power connectors it requires are not easily distinguishable, causing many people to damage their boards by not connecting it properly. This motherboard design lasted a long time, from the Pentium P5 to the Pentium 2 years, ushering in new technologies that have made it easier to swap components and integrate more drives.
Baby AT motherboard
In 1985 IBM released a smaller and cheaper motherboard design, the Baby AT, which without hesitation caused other manufacturers to switch to this variant as well. The specification of this model is very similar to that of the IBM XT motherboard, but with some modifications such as the position of the screw holes in order to fit into an AT type case.
Baby AT motherboards fit all types of cases except low profile or extra slim. As improvements, it presents the flexibility of its design, this point being the center of its success and drawbacks at the same time. Expansion slots are usually located on the left rear of the board with the microprocessor facing them. It was a valid point when the chips were slow and dissipated little heat, however the increase in speed of the microprocessors forced the incorporation of components with the capacity to cool them as much as possible. New components often prevent the installation of larger expansion cards, blocking some of the slots. The same design of the Baby AT motherboard
makes it difficult to integrate other components such as local network support, graphics controller or sound controller. Another factor against it is the maintenance or updating of certain components. It is uncomfortable to have to disassemble half a computer until you can reach any component in a more accessible way. It becomes somewhat hard and uncomfortable having to untie an entire plate to keep it in perfect condition. Generally, this maintenance nonconformity happens with memory sockets, since they are covered by a tangle of cables or even by storage units. Years of experience have helped some manufacturers successfully address these issues. However, there are still boards that present strange behavior errors against certain programs or operating systems.
Domain of a decade
After its launch, many manufacturers opted for this motherboard design. What attracted the most attention was his
220 x 330 mm size. So it dominated the market for a decade beyond the difficulties it created with the advancement of microprocessors. This variant of the AT form factor was in the personal computer market from the Intel 80286 series of processors until the introduction of pentiums. It was standard for personal computers until 1995 when it was replaced by the ATX form factor. Among the characteristics that his mastery stands out is that the motherboards built according to this design were the first to include connectors for different integrated ports, on the back and connected internally. Also, let's remember that the AT form factor was the first successful attempt at standardization for motherboard shapes. From there, the doors to a world of technological couplings were opened. Be the
form AT or Baby AT (in improved version), this factor created by IBM remained a leader until 1997. Since then, other more advanced models have emerged, not only from IBM, other manufacturers have taken on the task of creating their own motherboards and in many cases they are compatible with other components from different brands. Well, that was the intention from the beginning for clone manufacturers.