As someone who has been into audio almost as long as I have been into computers, my perspective is more technically informed about the compromises with integrating these two.
First off, a soundcard and a DAC are not the same thing. A soundcard and an external DAC are similar in many ways but the key feature that makes a soundcard different from an external DAC is that
a soundcard has a DSP. Also by "soundcard" that can include on-board audio since effectively the only difference is where it is physically, but as to how they operate, it'll be similar (see below for how this can be a problem). Some on-board and some soundcards though use a combo DSP-DAC chip similar to how smartphones have a combo DAC-(low voltage)HPamp chip and then runs the DSP mostly via software on the CPU.
That DSP can be used in concert with an external DAC. This way DSP features will be implemented on the signal. In most cases all the other DSP tricks are better implemented via software nowadays. Used to be you had to use an EQ on the player app and none for Windows, so your soundcard or on-board audio suite will hadle global EQ. But now there's Virtual Surround. The problem is how this is implemented. DSP on the soundcard doesn't send the sound back after processing it (unless it's an input that has to go somewhere, like if someone talked about what they did to the other player's mother, then that signal has to go through the mic input, ADC chip, then the DSP, then the processor, then out the computer and into the internet all the way to the "noob" with a mother who supposedly gets ridden like the town horse at the other end), which is why hardware DSP typically does not work via USB.
Even the ones on the motherboard don't, unless it's fully software implemented like Razer Surround. Even my new laptop can't run Dolby Headphone out via USB, which means it's not totally software but runs on the combo DAC-DSP Realtek chip.
The problem with using this Burson DAC-HPamp with a DSP - whether it's on the soundcard or the motherboard - is that USB bypasses that DSP chip. Which means you can enable hardware virtual surround all you want, you're not getting it, even with a fancy pants motherboard that is 7.1 capable, has digital output via SPDIF, and has drivers for DSP or virtual surround,
because this Burson DAC-HPamp only has USB input. You invested on a nice motherboard, which is great, but then you also bought this to drive a hard to drive headphone....but now you need a Razer Surround subscription negating that SPDIF digital output and drivers for DSP or virtual surround on the motherboard that you can't use via USB.
I personally would
not use them together, but that's because for a variety of reasons I
do not use my gaming rig for reference listening. Primarily because it's noisy - fan noise even at idle is still audible compared to a totally fanless music server. And even with efficient power supplies running efficient CPUs and a GPU at idle, there's still a giant screen I don't need for reference listening. So to get around the need to have a headphone amp or DAC-HPamp at my gaming rig, I just use a headphone that can be driven well enough by a soundcard - high enough sensitivity and high enough but not too impedance - so I won't need the specs of your Burson or this new one to get loud enough on it. And while I'm sure I'm piling on enough distortion even without clipping, high THD is a lot less of a problem when what I'm hearing are MP3 SFX and some guy talking about what he claims to have done with my mother where the really important audio feature anyway is virtual surround.
However what I am pointing out as the problem here is that 1) you can't use its features with that modern motherboard with a built in sound card that is 7.1 capable, has digital out, and has drivers for DSP or virtual surround, because the Burson only takes USB, on top of which 2) it's harder to use it mounted in a 5.25in slot on a chassis when modern PC cases either got rid of that feature or only have them in the interior with no removable covers on the front (ie, they're for only for platter hard drives or reservoir in that form factor, not optical drives or even card readers).
I know it does. My point was that I don't see anybody actually using it that way because 1) modern chassis designs got rid of the 5.25in slots or an external access (and thus use them only as 3.5in HDD caddys) on top of which 2) anyone actually using this with a fullsize computer would likely be using it more as a gamer than a sound producer (since the latter would likely have an interface with the DAC and ADC circuits necessary for recording) which is problematic if for example you want a better motherboard for both overclocking as well as audio, because now the audio bits on the motherboard - even the DSP chip - won't work with the Burson via USB.
There's still going to be considerable bulk in there though. So again, what cases can this be used in? The new Cosmos? Whoops, just lost some radiator spots.
It's a cool option, I really just can't see many people using it that way, and personally the bigger problem still is whether it can work with a motherboard's DSP at least. There's an extra port in there but the blurb doesn't explain what it's for. If it can hook up to PCI-Ex slot then maybe it can use the motherboard's DSP. Maybe.
Except there are two problems. Audiophile sound is more of "very clean signal with a lot of or at least enough excess power to drive a transducer louder with no noise, no distortion, no clipping." Gaming sound is positional audio - whether for competitive games or just for enjoyable immersion.
And in most cases while a good DAC-HPamp can render a soundcard obsolete, not when 1) you can't get virtual surround and when 2) the PC's cooling system renders it as a reference audio transport obsolete. Not even Noctua and BeQuiet! can get around that. It can be out of mind for the most part but if there's a noise floor, there's still a noise floor that can get in the way of how one hears music, especially the bass region, where headphone and speaker drivers tend to roll off, further complicating the problem. On top of which, most modern cases that lock away intake fan noise probably don't have 5.25in slots with access from the outside, so there's that problem again with a cool feature that I can't see being used. The
one case that can render Noctua and BeQuiet! obsolete also does not have a 5.25in slot for this device (on top of which, it costs $600, and running costs of ownership can include trips to the chiropractor), but again you'll have to use Razer Surround or whatever is built into the game (so it's gonna suck if you're not exclusively playing games that have virtual surround built in or bought a motherboard with a decent DSP).