atx

ATX (Advanced Technology Extended) is a motherboard and power supply configuration specification developed by Intel to improve on previous de facto standards like the AT design. Originally released in July 1995, it was the first major change in desktop computer enclosure, motherboard and power supply design in many years, improving standardization and interchangeability of parts. The specification defines the dimensions; the mounting points; the I/O panel; and the power and connector interfaces among a computer case, a motherboard, and a power supply.

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