Sound cards are all but extinct now, which seems odd since they used to be an essential part of any high-end PC build. Now they're a niche inclusion only for those with money to burn or for specific uses, and the space they once used to occupy has been overtaken by alternative parts. So what happened to sound cards, and why did they die out?

What were sound cards?

An integrated DAC/headphone amplifier inside your PC

For those who don't remember the joys of 90s and 2000s computing, a sound card was an added PCI (or AGP) card for your PC. These cards offboarded all of your sound processing and often provided a range of outputs, sometimes even including optical or surround sound outputs at the high end. Companies like Creative, Gravis, and even the likes of Turtle Beach cut their teeth by making PC sound cards. High-end sound card options could be a significant part of your budget for building a top PC at the time.

Depending on your age, you might remember classic sound cards such as the Creative Sound Blaster 16 and Creative Sound Blaster 32, the ubiquitous AWE32 and AWE64, or more modern alternatives like the Creative Sound Blaster Audigy 2 (my personal first sound card). You might even remember some sound cards coming with front-panel add-ins, which added volume control or other controls to the front of your case.

Modern sound cards do still exist. The Creative Sound Blaster AE-7 or AE-9 are common recommendations for gamers looking to upgrade their audio, but you probably don't actually need one for your PC.

Why did sound cards exist?

Motherboard audio just wasn't very good at the time

A big part of the initial success of sound cards was that even if your motherboard did feature onboard audio, it probably wasn't very good. Low-quality DACs (digital-to-analog converter), poor voltage regulation, and sometimes poor standard support, left onboard motherboard audio lacking for many. Hissing was a common problem, and high-resolution audio wasn't supported at all. Motherboards at the time often didn't have plentiful features; over the past few decades, there's been a centralization of features onto the motherboard over time. The obsolescence of previously common items like network cards, IO cards, and Wi-Fi cards comes to mind here. Part of the reason for this was technical. Motherboard design was in its relative infancy, and designing and manufacturing boards capable of providing buses and power distribution for five or ten separate different onboard chips, alongside expansion slots and required components for the PC, was difficult. It seemed especially far-fetched when keeping a budget in mind.

Interference and isolation were a problem

Even once onboard motherboard audio started improving its standard, problems with isolation and interference persisted. Part of this was poor quality voltage regulation, and persistent hissing was still present on some motherboards that either failed to ground properly, or failed to properly isolate onboard audio components from higher voltage buses nearby. This problem was slowly solved, and various solutions for isolating onboard audio were significant selling points for motherboards as late as the mid-2010s. Hilariously, in retrospect, these problems were often worsened by other devices being connected to your PC, leading to forum posts that complained about popping sounds when a USB device is plugged in or persistent hissing only while typing.

This is still something motherboard manufacturers need to deal with, but over the years, designs have improved significantly, and it's a far rarer issue now. Quality control has also improved significantly, and you're less likely to get a dud board with bad isolation even if there's not strictly a flaw in the underlying design.

Sound cards freed up CPU cycles

This one looks a bit further back into PC history, but a significant issue for demanding games in the '90s and early 2000s was that audio was computationally expensive. While this part of it is abstracted from you, a game's audio is often a complex series of layers with mixing and effects. It also does the heavy lifting of converting your digital audio to an analog output while also providing amplification. This was often compounded by more primitive OS scheduling, which was less adept at scheduling audio processing to avoid having a significant impact on framerates or input latency.

External sound cards also often provided significantly lower latency, which while rarely a problem now, was often an issue with lower-end onboard audio devices. Accompanying all of this was a range of proprietary 3D and high-resolution audio technologies, as well as games that pushed modern audio to its limits. External sound cards were often required for proprietary technologies supported by some games, like Creative's Eax extension in the late '90s or Aureal's A3D, both of which were supported by the original Half Life.

Sound cards often had extra features

It wasn't all doom and gloom for sound cards when justifying their existence, they did often include extra features that the motherboard simply didn't. This might be MIDI inputs or outputs, alternative connectors like optical audio, additional microphone inputs or, as we mentioned earlier, front-panel add-ins and external volume controls.

Modern sound cards still exist

External DACs have taken up the mantle

Sound cards do still exist but are mainly focused on the pro/prosumer audio scene. There are some good justifications for getting one. If you're looking for extremely low latency audio output, then a sound card can help significantly. External DACs have also blown up over the last couple of years, with companies like Schiit making a range of high-end DAC/headphone amplifier combos. These combos connect to your PC via USB (normally) and take over some of the responsibility once put on sound cards: to convert digital to analog audio, while also often providing integrated headphone amplifiers.

These DACs are one of the ways to level up your audio game, especially if you've got other high-end audio gear or want outputs like optical.

Sound cards aren't coming back anytime soon

There's been a general trend of more and more features being integrated into admittedly ever more expensive motherboards, and this isn't a trend that will be reversing any time soon. There are some upsides and downsides to this for the consumer. Upgrading to a better CPU or chipset now often requires you to re-purchase all of this hardware together, essentially replacing your Wi-Fi chip and sound card at the same time. Basic versions of these components have become affordable enough that you could buy external ones and move them between cheaper motherboards lacking these features for relatively little cost. We certainly think the loss of complexity in dealing with multiple additional add-on cards is a big win for consumers. The feature-rich boards we enjoy now may even be a small part of why building custom PCs has become so much more approachable over the last decade.