An extended ATX motherboard is a larger version of the ATX motherboard. They are typically used in servers and high-end gaming computers. An extended ATX motherboard can have up to 12 memory slots, while a standard ATX motherboard only has four.
They also support more PCI Express slots, which are used for graphics cards and other expansion cards.
An extended ATX motherboard is a type of computer motherboard that offers more features and expansion options than a standard ATX motherboard. An extended ATX motherboard is typically 12 inches wide by 13 inches long, which is about 2.5 inches longer than a standard ATX motherboard. The extra space on an extended ATX motherboard provides room for additional expansion slots and other features.

Credit: www.newegg.com
What is the Difference between Atx And Extended Atx?
There are two main types of PC motherboards- ATX and Extended ATX. Both these motherboard form factors offer different advantages and disadvantages. Here is a quick comparison between the two to help you choose the right one for your needs:
ATX:
Advantages:
+ More affordable than Extended ATX boards
+ Generally smaller in size, making them easier to install and transport
+ Better suited for building smaller PCs
Disadvantages:
– Limited expandability compared to Extended ATX boards
Extended ATX:
Advantages:
+ Offers more expansion slots and room for additional features compared to an ATX board
+ Ideal for building high-end gaming PCs or workstations that need maximum expandability
Disadvantages:
– More expensive than an ATX board
What is Extended Atx Case?
An Extended ATX (E-ATX) case is a type of computer case that is designed to fit motherboards that are larger than the standard size. These cases are typically used for gaming computers or workstations that require more expansion room than a standard ATX case.
Extended ATX cases are usually wider and deeper than a standard ATX case, and they often have additional features such as more drive bays and expansion slots.
Many E-ATX cases also come with built-in liquid cooling systems to help keep your components cool.
If you’re looking for an E-ATX case, be sure to check the dimensions of your motherboard to make sure it will fit. Some E-ATX cases can also accommodate Standard ATX and Micro-ATX boards, so they may be a good option if you’re planning on upgrading in the future.
What Size is Extended Atx?
Extended ATX, also known as eATX, is a motherboard form factor that is often used in high-end servers and workstations. The size of an eATX motherboard is 12″ x 13″, which is slightly larger than a standard ATX motherboard (12″ x 9.6″). While the extra size may seem like a wasted space at first glance, it actually allows for more expansion slots and additional room for cooling components.
One of the main reasons why eATX motherboards are often used in servers and workstations is because they can accommodate more expansion cards. For example, an eATX motherboard might have 7 PCI slots while a standard ATX motherboard only has 4 or 5. This means that you can add more devices to your system without having to replace the entire motherboard.
Additionally, the extra size also provides better airflow around the chipset and other heat-generating components. This helps to keep your system cool and stable, even when under heavy load.
If you’re looking to build a high-end PC or server, then an eATX motherboard should definitely be on your radar.
Just keep in mind that you’ll need a larger case to accommodate this larger form factor.
Is My Motherboard Atx Or Eatx?
When it comes to computer motherboards, there are two main types: ATX and EATX. So, which one do you have? Here’s how to tell the difference.
The first thing you’ll need to look at is the size of the motherboard. An ATX motherboard measures 12 inches by 9.6 inches, while an EATX motherboard is a bit larger at 12 inches by 13 inches. So, if your motherboard is on the larger side, it’s likely an EATX model.
Another way to tell the difference between ATX and EATX motherboards is by looking at the number of expansion slots. An ATX motherboard has seven expansion slots, while an EATX motherboard has nine or more expansion slots. So, if you’re planning on adding a lot of extra components to your computer, you’ll need an EATX motherboard to accommodate them all.
Finally, take a look at the power connector on your motherboard. An ATX power connector is 20-pin, while an EATX power connector is 24-pin. If you’re not sure which type of power connector you have, consult your computer’s manual or look up its specifications online.
So, now that you know how to tell the difference between ATX and EATX motherboards, which one do you have? If you’re not sure or if it doesn’t matter to you (for example, if you’re not planning on adding any extra components), then either type will work just fine for your needs.
"E-ATX" Is A Lie: How Motherboard Makers Ruined Form Factors
Will an Atx Motherboard Fit in an Eatx Case
Assuming you’re talking about computer cases and motherboards, the answer is usually no. ATX is a standard size for motherboards, but EATX is a bigger size designed for servers and high-end gaming PCs. So an EATX case probably won’t fit an ATX motherboard.
However, some manufacturers make cases that can accommodate both sizes of boards.
Conclusion
An extended ATX motherboard is a larger version of the standard ATX motherboard. They are typically used in high-end gaming computers and workstations. Extended ATX motherboards have more expansion slots and allow for more powerful components to be installed.
They are also often used in servers due to their increased expandability.