PC Jr/Tandy 1000 - The first enhanced audio capabilities given to any sort of IBM Compatible PC on a large scale, was the IBM Personal Computer Jr. model 4860 released in early 1984. The machine was a flop, but featured a 3-voice square wave sound chip ON TOP pof the PIT monophonic audio. This was provided from a Texas Instruments SN76489 audio chip. However, despite it's flop, it's advanced features carried on in Tandy's 1000 series desktops up until the early 1990's, adding Digital Audio to it sometime later. It's most common usage today is on Tandy 1000 systems for Retro-Gaming old Sierra AGI and Taito Arcade ports since they sound best on the PC Jr/Tandy 1000.

MPU-401 - MPU-401 is really a standard sound I/O function of MiDi. Unlike the others in this list, an MPU-401 card interfaces with external synthesizers via MIDI, as well as external modules, allowing you to tailor your own sound entirely based on what hardware you are using. This was likely a common option with Musicians.

Creative Labs GameBlaster - The Creative Labs Gameblaster was an early 3-voice, square Wave audio card that sounded a lot like the Tandy 1000/PC Jr. Audio Circuit, but worked with a wider array of software and applications. It too was based on a Arcade Machine type audio chip.

Covox/Disney Sound Source - This was an external device that attached to your PC's Parallel Port and could play digital audio through it. It has since been reproduced by hobbyists, but it also is a rare piece of computing history. It looked like a speaker with a printer cable attached to it, basically.

Adlib - Adlib was a sound standard based around the Yamaha OPL FM Synthesis chips such as the YM-262 (OPL/3). These cards sounded like late 80's Yamaha PortaSound Keyboards (PSS/PSR series) because they used the EXACT SAME CHIP in a lot of cases. Adlib would continue to live on up until the end of the 1990's as a part of many PC sound Cards based on the SoundBlaster and Windows Sound System (WSS) Standard.

Roland MT-32 - Roland MT-32 was a high end sound card standard from the late 1980's that used Wavetable Synthesis to achieve a higher quality FM Synthesized audio. This resulted in some extremely good sound quality sounding very close to real instruments.

Creative Labs SoundBlasterProbably the best known sound card ever. The Creative Labs SoundBlaster was a 8-bit (later 16-bit with the SoundBlaster Pro 2.0 and 16 cards), Digital Audio capable sound card with an Adlib-based audio option built in for music. SoundBlaster cards started to become the most popular and later domineering standard for the rest of the 1990's until DOS gaming ended entirely, and people were using full-blown digital audio on their PC's for everything (AC97, Intel Integrated Audio). Many clone chipsets popped up such as those by Aztech, Analog Devices, Crystal Semiconductor, and ESS.

Windows Sound System - Windows Sound System was a standard SIMILAR to Creative Labs soundblaster, except instead of a proper DAC AUdio Chipset, it used an "Audio Codec" chip - usually an Analog Devices AD1886 or a Crystal Semiconducter CS-4231-series chip. Actual cards often contained a proper Adlib chip for FM synthesies along side the 44.1KHz 16-bit CD Audio Quality codec, but a lot of Laptops from the early-mide 1990's in the 486 era had these chips WITHOUT the synth.

Roland Sound Canvas - Another series of devices by Roland, a well known Synth Maker, most of which were attached externally much like MPU-401. These included the SCP-55 and other synths, and offered finer control over the sound of the synthesizer than previously offered such as envelopes, dynamics, and whatnot. I don't have a lot of experience with this one.

Gravis UltraSound (GUS) - Another Sample-Based Wavetable music synthesizer card released in the early 1990's and also well sought after. I don't have a lot of experience with this one either.

When Vintage IBM Compatibles really started to take off in the early 2010's, a lot of aspiring Electronics Engineers and hobbyists took to designing their own sound card "products" to either sell or allow people to copy via OpenSource for their vintage machines. A lot of this was to address the shortcomings of such systems such as the IBM PS/2 with it's proprietary MicroChannel Architecture, old Laptop Computers without PCMCIA thusly no way of audio expansion, and even some newcomers are working on PCMCIA Sound cards now because they are so hard to get and so rare.