The motherboards come in different sizes and shapes. ATX, Mini ITX, and ITX motherboards are a few examples of motherboard dimensions. A form factor is a motherboard with standardized specifications and dimensions.
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In today’s post, we will try to find some details on the AT motherboard form factor and understand enterprise SSI CEB standards.
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The AT motherboard was initially developed by IBM and was introduced in the 1980s. Intel later standardized this with the now common ATX form factor. The correct dimensions of an ATX motherboard are 12 in × 9.6 in (305 mm × 244 mm), while there may be a few differences.
The ATX form factor was developed for the single processor system. However, the motherboards are produced in several form factors based on the individual requirements and specifications.
The motherboards are available in different form factors. Several parameters dictate the form factor of a motherboard.
A few of these parameters would include size, shape, mounting holes, power supply, and other features.
In recent times, manufacturers introduced the “EATX” form factor. Although it implies a standard, it’s not a standard at all.
EATX is 12″ by 13″ wide if it’s evenly defined, while a standard ATX board is 12 inches tall and 9.6 inches broad.
Other organizations have periodically taken it upon themselves to complicate things, as with Supermicro’s EE-ATX, which means “Enhanced Extended Advanced Technology eXtended.” Then there’s XL-ATX, a name that EVGA, Gigabyte, and MSI have abused to depict three nearly-identical motherboard sizes.
Let’s not bypass BTX, or “Balanced Technology eXtended,” a standard measured 10.5″ x 12.8″
Things would be a lot more straightforward for everyone if motherboard manufacturers adhered to the dimensions of SSI-EEB without trying to wedge custom form factors in between or accurately referred to 12″x10.5″ boards as SSI-CEB, but that’d require trying to follow a standardized spec.
Accordingly, you would find a wide range of motherboards with different specifications such as eATX, ATX, microATX, SSI CEB, SSI EEB, SSI MEB, COM Express, or a custom form factor that the manufacturer may decide.
As stated, the ATX motherboard was designed to work with the single processor system. Enterprise Electronics Bay Specification (EEB) further standardized and improved this. The specifications under the EEB were developed from the ATX specification.
The EEB specification was designed to address a wide range of areas in terms of computer technology. Some of these areas would include support for the dual-processor systems.
You would also find it an excellent option for the functionalities such as support for current and new chipsets. The support for multiple processors and memory control options made the SSI specification a great choice.
The EEB standards further gave way to the SSI CEB systems. The SSI CEB system stands for Server System Infrastructure (SSI) CEB specification.
CEB stands for Compact Electronics Bay Specification. The form factor is specifically designed to work with the dual-processor motherboards. The standard specifications for the CEB motherboards are 12 x 10.5 inches (305mm x 267mm).
The CEB requirements were first introduced for the value servers and workstations based on the Intel XEON processor. The Xeon processors work with multiprocessing or in a multi-socket-capable environment. Developed by Intel, it is an x86 microprocessor. The processor is designed for working with a business or engineering server, workstation, or embedded system markets.
The CEB motherboards are designed with an architectural structure comparable to ATX IO connectors. In addition, they come with the same motherboard mounting holes equivalent to those on the ATX motherboards.
The only difference is that the motherboards are more significant than the ATX motherboards. You would also find some changes, such as unusual processor mounting holes.
In most scenarios, you would find that the rear opening on both the CEB motherboards and ATX motherboards is the same. You would also find that the expansion slot on SSI CEB motherboards is similar to those on the ATX motherboards.
In essence, the SSI CEB is slightly bigger than the ATX but smaller than the Extended ATX/ SSI CEB form factor.
The form factor for the motherboard was not a concern just a few years ago. The form factors were created for or based on the ATX model.
This was just designed considering one processor design in mind. The development of the XEON processor mandated the need for the CEB design.
This also created the best possible playing field for ATX and the EEB. As a result, the CEB specification primarily provides you access to a great degree of performance excellence in terms of multiprocessor environments.