Editing Sound card (section)

===Integrated sound hardware on PC motherboards===
In 1984, the first [[IBM PCjr]] had a rudimentary 3-voice sound synthesis chip (the [[SN76489]]) which was capable of generating three square-wave tones with variable [[amplitude]], and a pseudo-[[white noise]] channel that could generate primitive percussion sounds. The Tandy 1000, initially a clone of the PCjr, duplicated this functionality, with the Tandy 1000 TL/SL/RL models adding digital sound recording and playback capabilities. Many games during the 1980s that supported the PCjr's video standard (described as ''[[Tandy-compatible]]'', ''Tandy graphics'', or ''TGA'') also supported PCjr/Tandy 1000 audio.

In the late 1990s, many computer manufacturers began to replace plug-in sound cards with an [[audio codec]] chip (a combined audio [[analog-to-digital converter|AD]]/[[digital-to-analog converter|DA]]-converter) integrated into the [[motherboard]]. Many of these used [[Intel]]'s [[AC'97]] specification. Others used inexpensive [[Advanced Communications Riser|ACR]] slot accessory cards.

From around 2001, many motherboards incorporated full-featured sound cards, usually in the form of a custom chipset, providing something akin to full [[Sound Blaster]] compatibility and relatively high-quality sound. However, these features were dropped when AC'97 was superseded by Intel's [[Intel High Definition Audio|HD Audio]] standard, which was released in 2004, again specified the use of a codec chip, and slowly gained acceptance. As of 2011, most motherboards have returned to using a codec chip, albeit an HD Audio compatible one, and the requirement for Sound Blaster compatibility relegated to history.