Intel High Definition Audio

[1] The Intel High Definition Audio specification includes the following features:[2] Motherboards typically do not have any more than eight built-in output channels (7.1 surround sound) and four input channels (back and front panel microphone inputs, and a back-panel stereo line-in).

Retrospective UAA drivers were also built for Windows 2000, Server 2003 and XP Service Pack 1/2.

Several Linux operating systems also support HD Audio, as well as OpenSolaris,[4] FreeBSD,[5] and OpenBSD.

[7] Configurations of the host controller (Chipset) are available from third-party suppliers, including Nvidia, VIA and AMD,[7] while codecs have also been provided by third-party suppliers including Realtek, Conexant, IDT, VIA, SigmaTel, Analog Devices, C-Media and Cirrus Logic.

[8][9] AMD's TRX40 chipset was introduced in 2019 for use with Ryzen "Threadripper" CPUs, which provided the Realtek ALC1220 chip instead of the HD Audio interface.

Intel provides a general specification for this process, but the signal assignments are different for both AC'97 and HD Audio headers.

When a plug is inserted, the isolated switch inside the jack informs the motherboard, and the codec sends audio to the headphones.

In addition, software must be aware that an AC'97 dongle is being used with an Intel HD Audio analog header since the software might need to dedicate codec ports that are connected to the header to meet the product's intended functionality.The different signal assignments can cause trouble when AC'97 front-panel dongles are used with HDA motherboards and vice versa.

Consequently, a loud audio passage may cause a HDA motherboard with a AC'97 dongle believe headphones and microphones are being plugged and unplugged hundreds of times per second.