Most Popular Motherboard Form Factors for Embedded Design

motherboard form factors sizes

What is form factor?  

When it comes to hardware, certain pieces are designed with a certain size in mind. Through these specific designs, they dictate certain specifications. In a computer, many pieces of the internal hardware, such as the motherboard, storage drives, and even memory come in a wide variety of different shapes and sizes, also known as form factor. Form factor is the hardware design that describes the shape, size, and other physical specifications that define components.  

Form factor may represent the actual size and shape of certain products or represent a certain physical design of a component. For example, SSDs have a varying representation in both size and in their physical design that changes their connection type (2.5 SATA, mSATA, or M.2). Both represent the storage drives form factors. In this case, both are related to one another.  

Different types and sizes of motherboards

One of the most common pieces of hardware that carries a multitude of form factor variations is the motherboard. A motherboard is the main printed circuit board, and as the name suggests, it is the ‘mother’ piece that allows for communication between many of the crucial electrical components in a computer system. Motherboards come in a variety of form factors, and each type of motherboard size is designed based upon the size limitations that they will fit into, whether it is a desktop computer, laptop, or a rugged edge computer. The form factor will also designate the locations of the mount points, the I/O panel, the power connectors, and all other various connection interfaces. 

There are many types of motherboard form factors that are currently in use today. And while there is a large amount of form factors, many of them are obsolete or designed for a very specialized purpose. For the purposes of this article, we will explore ones that are the most prolific in the consumer and industrial world. 


The most common form factor that many people will see and use is the standard ATX (Advanced Technology Extended). The ATX was developed to succeed the AT/Baby AT motherboard that drastically changed in architecture. This is among the most popular form factor in commodity motherboards. Created by Intel in 1995 and is about 9.6 inches by 12 inches, this type of motherboard is commonly found in many desktop computers around the world due to its efficiency in performance. Upon glance, it is easy to see why this size has been so dominant over the years for users. ATX motherboards offers room for many I/O ports, PCIe lanes, and SATA connections that all enthusiasts can find useful for many purposes. The ATX motherboard also introduced sleep mode in power management, allowing users to put their systems in a low powered mode and resume their work right where they left off. Since 2017, the ATX has been the de facto standard for many PCs today. 

Micro ATX  

A smaller variation that was based upon the ATX motherboard, the Micro ATX is the successor to the standard ATX. Slightly smaller in size, the micro ATX was designed to be backwards compatible with ATX sized cases. Many of the components that fit into a standard ATX also worked with the microATX, with the only big difference being the amount of expansion slots that the microATX could fit (a maximum of 7 in standard and 4 in micro). As with all downsizes, the micro ATX is a popular choice for those who favor cost-savings over expandability. 

motherboard size comparison

(Image source: Wikipedia)

Small Form Factor Motherboards 

Moving away from the ATX family, introduces ITX, or information technology extended, motherboards. ITX Motherboards are a family of small form factor motherboards that was created by VIA Technologies in 2001 for use in small configurations. ITX boards were purpose built for compact small form factor PCs, with several components slots drastically reduced to fit within small spaces. Small form factor motherboards also come in a variety of sizes that are aimed at the embedded market.  


The mini-ITX was the first of many ITX sizes that were designed for compact applications, especially ones you can find in the embedded space, ranging from in-vehicle computers to industrial automation. It became a popular choice due to its ability to fit into physically space constrained areas, low power consumption, and passive cooling through heatsinks.  

Nano-ITX, Pico-ITX, 3.5” Industrial Motherboard, & FEMTO-ITX 

Following the mini-ITX is a whole succession of smaller sized ITX motherboards that are designated as some of the smallest sized motherboards. Here many of these motherboards are fully integrated, meaning that many of the components, like the CPU and various other controller cards, are built right onto to the motherboard, rather than using expansion slots or installable components. A single board computer is a prime example of a fully integrated system design where many of the important components are soldered right onto the board to allow for a reliable and power-efficient solution. 


Nano ITX is the first of these smaller ITX boards that was introduced in 2003 (also by VIA Technologies). Nano ITX motherboards measure 12cm x 12cm (4.7 inches) and are fully integrated with very low power consumption. At this size, many of these motherboards are directly used for smart entertainment and in-vehicle devices.  

3.5” Industrial Motherboard 

3.5 inch industrial motherboard single board computer

The first step off the path of standardized form factors. A 3.5” industrial motherboard is one that is designed to be the same size as a 3.5” hard drive disk. Although small, it is made with a rich I/O that fits into a wide range of industrial applications. What is confusing, however, is that the 3.5” is not actually 3.5” in area. Rather, the sizing is actually 5.75” x 4”. As stated, it takes its name from the 3.5” HDD, which surprise, isn’t also 3.5” in area. This interesting nomenclature draws its roots back to the days of the floppy disk, where the diameter of the metal disc was 3.5” in size. 


Pico ITX, also developed by VIA Technologies, is half the area of the Nano ITX sitting at 3.9in x 2.8in in size. This is the smallest size in the series of ITX boards developed by VIA. The Pico-ITX was created to open doors for further innovation into the smallest and smartest IoT devices. Reaching this point of miniscule size to deliver performance with a low TDP creates new opportunities for services that were not previously possible. PICO-ITX SFF motherboard is specifically designed to bring the performance of x86 or 32-bit CPU and operating system to an embedded system at only under 10 watts TDP design.   


femto Itx 1.8 inch industrial motherboard

FEMTO-ITX is the newest and smallest form factor listed within this article. This extremely compact size is roughly the same size as a credit card and is designed for the most space constrained applications. As with the pico-ITX, FEMTO-ITX opens even more avenues for innovation in compact designs in the rugged edge. FEMTO-ITX can be compared with the off-the-shelf DIY Raspberry Pi in size and functionality. However, with a FEMTO-ITX, it is more geared for industrial applications for its versatility in I/O.

 Form Factor Dimensions Applications PCIe Slots

Standard ATX

12 × 9.6 in

Desktop PC  2-3x PCIe x16 
2-3x PCIe x1 
Micro-ATX 9.6 × 9.6 in Small Form Factor 

1-2x PCIe x16 
1x PCIe x4
1-2x PCIe x1 

Mini-ITX 6.7 × 6.7 in  Small Form Factor

1x PCIe x16
1x Mini PCIe

Nano-ITX 4.7 × 4.7 in  Embedded System

1x PCIe x16
1x Mini-PCIe 

Pico-ITX 3.9 × 2.8 in  Embedded System 2x Half-sized mini PCIe 
3.5" Motherboard 5.7 x 4 in  Embedded System 1x Mini PCIe 
FEMTO-ITX 3.3 x 2.1 in  Embedded System 1x Mini PCIe 

What are Industrial Motherboards and How are they Different?   

industrial motherboards single board computer integrated motherboard

When it comes to the rugged edge, it is difficult to make a standard component like an ATX motherboard fit into an industrial setting. Many applications are constrained by limited space and make it hard to put together a complete system the size of a desktop computer. Alongside this, many industrial applications are subject to harsh conditions, ranging from extreme temperatures, shock, vibration, dust, and debris. In many of these cases, these harsh environments make it difficult to maintain a proper system in both power and performance. In these areas, a system needs to be low in power consumption, yet still output enough to perform compute solutions.  

These applications can range from industrial automation, vehicle automation, smart kiosks, digital signage, medical imaging, casino gaming, and security/surveillance. And it is within these applications that you find the most use for the small form factor motherboards. Small motherboards are small enough while still being able to provide the sockets for flexibility in processing performance. Moreover, smaller form factor motherboards like the 3.5" motherboards utilize a Single Board Computer (SBC) design, which combines all computer components in a single substrate. SBCs tend to be low powered, making it an ideal solution for entry-level industrial workloads that require just enough power consumption and performance. The advantages that small form factor motherboards have compared to standard commercial ones are as follows:  

  • Size: It’s easy to see the difference, but size is a major factor in industrial applications. Many areas simply cannot fit large PCs to perform the necessary tasks needed in industrial settings. Having a smaller size that can output the necessary performance makes the world of a difference.  
  • Power efficiency: Many small form factor motherboards and PCs do not generate as much heat as normal ones do. The low processing power helps promote a long-life span and reduces the operating costs in cooling, as many applications utilize passive cooling through heatsinks 
  • Longevity: As mentioned previously, industrial motherboards carry a long-life span. All parts are specifically chosen to deliver a long life without the need for replacement or maintenance. By doing so, it reduces the total cost of ownership and potential RMAs. 
  • Durability: Industrial motherboards are built to last and built to withstand. Many industrial settings are harsh and require careful planning and design to withstand the hardest deployments where dust, debris, water, shock and vibration all take place.  

Industrial motherboard’s simple and effective design makes it easier to use and eliminates all the unnecessary add-ons that are found in commercial ones. It is important to consider the features to match the various types of deployments.  

Premio’s Line of Industrial PCs, Motherboards, and SBCs 

premio family product industrial pc and industrial motherboard

Premio’s product line of single board computers and industrial PCs utilizes not only common small form factor motherboards but also our own design of motherboards that fit within our respective products. All of our industrial PCs and motherboards are designed to tackle the very obstacles that come with deploying at the rugged edge. Our products are the building blocks for many industrial applications that require reliable computing solutions to manage many complex workloads in the most rugged and harsh environments. 

Our family of fanless embedded computers are purpose built, validated, and certified to operate in wide temperatures, voltages, and shock and vibration standards. Edge computing devices come in a variety of different types that include, mini IoT gateways, fanless edge computers, and industrial grade embedded computers.

Learn more about our Industrial and Rugged Edge Computers.

Premio’s industrial motherboards represent the fabric of embedded computing. Premio provides reliable and long-lasting standard off-the-shelf motherboards for the most challenging embedded applications. Premio also provides end to end services to help configure and solve design challenges. From a custom solution to a small change in I/O, we can adapt each motherboard into a solution that complies with the right specifications without compromising performance. Our latest launch adapts AMD Ryzen Embedded SoCs into our 3.5” and 1.8” FEMTO-ITX single board computers to provide another option for x86 performance and I/O flexibility in a small form factor.  

Learn more about our Industrial and Rugged Edge Computers.

Why Premio? 

Premio is focused on providing reliability and flexibility to our embedded systems, industrial motherboards, and SBCs that OEM designers can integrate into their overall system. Our products are built rugged and built ready through thorough testing and validation in their performance and reliability against harsh environments.  

Premio has positioned itself to provide scalable manufacturing with our state-of-the-art facility in Los Angeles, CA and strategic locations in Taiwan, Malaysia, and Germany. Our goal is to provide localized support, rapid time-to-market, and complete manufacturing transparency for our core products in Embedded IoT Computers, Rugged Edge Computers, HMI Displays and HPC Storage Servers.

premio global manufacturing locations