Playback via server vs laptop?

For several years now I’ve been enjoying hi res audio- I have J River on a MacBook Pro going into my DAC. It works works well. What would I gain, if anything, in sound quality, from using a dedicated server such as one of the Aurender units, in stead of my MacBook Pro? 
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IMO, the USB output from a laptop is a flawed protocol for digital audio transmission because it is prone to noise and jitter issues. The USB output in a laptop is a multipurpose interface not specifically designed for audio. Unless you treat the jitter and noise externally before reaching into your system, it’s very unlikely to achieve SOTA digital audio reproduction. 

The dedicated audio server takes a methodical and much superior approach to output digital bits to a outboard DAC by eliminating jitter and noise.

Aurender, Auralic and Lumin servers includes legacy outputs (AES/EBU, SPDIF, Optical) as well as USB audio outputs and represent a superior method of audio transmission.

Antipodes and Innuos are among the most popular servers opted to focus on perfecting audio through USB output only.

I would suggest working with a dealer that would allow you to audition servers from aforementioned manufacturers and decide for yourself what sounds best to your ears and in your system.

With money to burn, get all the separated you want. I use a MacBook pro running Tidal-Audirvana into a Recovery reclocker. It works fine and I can simultaneously answer my email while bringing in the bacon... All on a budget
I jumped over to a network player on the cheap / homebrew route using a Raspberry PI and RuneAudio after my desktop's HD bit the dust.  I also started migrating my FLAC files over to a NAS device, mainly for backup.

If you are comfortable with some basic component assembly and copying files to a SD card using old DOS commands, this might be an option.  I went with a generic 32bit, but there are plenty of add-on DAC options in all price ranges.