microATX

microATX (also written as µATX or mATX) is a motherboard form factor developed by Intel in 1997 as an evolution of the ATX form factor. It is smaller than standard ATX, with maximum dimensions of 9.6 × 9.6 inches (244 × 244 mm). This smaller size allows for smaller computer cases, making it a popular choice for space-constrained environments and budget builds.

While smaller than ATX, microATX motherboards retain compatibility with many ATX components, including the power supply, CPU cooler mounting holes, and in some cases, expansion cards, though typically with a reduced number of PCI/PCIe slots. This backward compatibility provides a cost-effective upgrade path for users already invested in ATX hardware.

The reduction in size primarily affects the number of expansion slots (PCIe, PCI) available. A typical microATX board will have fewer slots than a full-sized ATX board, limiting the potential for adding multiple graphics cards, sound cards, or other expansion devices.

Despite the size reduction and fewer expansion slots, microATX still supports a wide range of CPUs, memory configurations, and integrated features, making it a versatile option for general-purpose computing, gaming, and media consumption. Its balance of size, features, and cost makes it a widely used form factor for desktop computers.