a consumer pc is a bad source and the fractal design cases are beautiful, but a poor choice for audio, because of the open design.
The differences between these LPS power supplies are huge. For me it was surprising what a well designed does, not a subtile change, but instantly audiable, more depth, better lows and more refined. You should be well informed before buying one.
Far too generalized statement. Sure, an off the shelf consumer PC or a Laptop are not a great choice, however you can indeed build a custom PC with very good results.
Then you need to fulfill to a few basics:
The Fractal Define 7 case is excellent. It is a quiet case, no noise and the Fans are all Noctua Fans including the CPU cooler. Noctua fans are extremely quiet, 11db. I use all shielded cables, the MOBO was made for audio with upgraded caps and the power supply is extremely low noise and low ripple and one of the lowest on the market at the time I bought it. I would put it up against most music servers in quality of sound. There is no noise coming from the case. My fans rarely spin up and when they do, you can't hear them. I researched and hand picked the parts for low distortion and quietness. I use mostly m.2 hard drives except for a couple of WD Reds which holds music that I rarely listen to.