The AT power supply form factor is considered the original standard for power supplies in desktop computers. It was introduced in the 1980s and was widely used until the mid-1990s. The AT form factor was designed to provide a standardized size and shape for power supplies, making it easier for manufacturers to design and build compatible systems.
History of AT Power Supply
The AT power supply form factor was first introduced by IBM in 1984, as part of their PC/AT system. The form factor was designed to provide a compact and efficient way to power the system's components, including the CPU, memory, and peripherals. The AT power supply was typically mounted in the rear of the system case, with the connectors and cables routed to the various components.
Key Features of AT Power Supply
The AT power supply form factor has several key features that defined its design and functionality. It typically measures 6 inches (15.24 cm) wide, 3.5 inches (8.89 cm) tall, and 5.25 inches (13.34 cm) deep. The power supply uses a combination of connectors, including a 6-pin P8 and P9 connector, to connect to the system's motherboard and other components. The AT power supply also uses a 115/230V AC input and provides multiple DC output voltages, including +5V, +12V, and -12V.
Advantages of AT Power Supply
The AT power supply form factor has several advantages that made it a popular choice for desktop systems. Its compact size and standardized design made it easy to integrate into system cases, and its multiple output voltages provided flexibility for powering a variety of components. The AT power supply also used a simple and reliable design, with a single fan for cooling and a basic voltage regulation system.
Limitations of AT Power Supply
Despite its popularity, the AT power supply form factor has several limitations that eventually led to its replacement by newer form factors. One of the main limitations is its relatively low power output, typically limited to around 250 watts. This made it less suitable for more powerful systems that required higher power levels. Additionally, the AT power supply's large size and weight made it less efficient and more difficult to cool, especially in smaller system cases.
Legacy of AT Power Supply
Although the AT power supply form factor is no longer widely used in modern systems, its legacy can still be seen in many areas of the computer industry. The AT form factor's design and functionality influenced the development of later power supply form factors, including the ATX and Micro-ATX form factors. Many modern power supplies still use similar connectors and output voltages, and the AT form factor's emphasis on standardization and compatibility has had a lasting impact on the industry.
