Audio PC

It is actually shocking how significant the impact of the digital server can be for sound quality.  I used a PC built to the specs of the second iteration of the CAPS server as my first digital server.  I upgraded to an Antipodes DX II and it had a nicely positive impact on the sound quality.  I was considering going up to their latest K50 to get even more when I came across the Taiko Audio Extreme thread and that persuaded me to go whole hog and try that.  I mean "Wow!" what an improvement in sound quality!  

So, IME how the "PC" is built for server duties is every bit as important as the DAC (or possibly more so).  YMMV.

I built a dedicated fanless Intel NUC powered by an Sbooster Mkll PSU for Roon Rock.From NUC to Router i use a Mad Scientist Black Magic LAN cable.Result is amazing!

Avoid any laptop or desktop computer that is inherently noisey. If you have a gaming laptop or laptop, I wouldn't use it for audio.

My Gigabyte Aero 17 is quite noisey. For that, I have an iFi silencer 3.0 that does wonders for it. Although it has a built in GPU, I undervolted the laptop and achieved 30% better performance and silent fans during music playback. 

Fanless laptops or desktop computers are ideal fo audio only applications. 

For music listening I use a QuietPC with SSDs. The constant 'noise' coming from the background processes in the computer which are not necessary for music reproduction can be brought down to the absolute minimum by installing Audiophile optimizer.Finally I configured my USB interface (DAC) so that it doesn't use the power over the USB cable from the PC but its own linear psu. Like this the PC and the DAC are galvanically isolated.For playing music I use HQPlayer 4 or a standalone studio production tool (like  Ozone 8 for instance) with which I can add virtual tape etc in real time. Very cool.

The biggest problems with using a PC is the noise,  When I was using my PC (I upgraded to an Aurrender and COULD NOT BE HAPPIER) the biggest issue was the noise form the power supplies and the crappy USB interface (USB sucks.  Its for peripherals - not music).  I got an ESI Juliet Sound Card and replaced the power supplies and it sounded good - but the ease of working it was annoying. You need to be a network admin to handle it.  The Aurrender was a game changer for me.  PCs suck for music. Leave them for work and get a real streamer.