Computer Upgrade

Whatever it is, I just find USB has no place in hi fi.

Back to the OP question. You can get a lot of views over at computer audiophile forum. I suggest staying with the operating system you are most comfortable with. I never tried a Mini, so can't compare the sound to a Windows machine. I've evolved within Windows machines, though, so I can comment on my experience with that.

My system used to be a Win 7 laptop with JRiver connected to an Audiophilleo with PurePower, connected to a Metrum Octave, tube pre and amp. Music library inside a USB hard drive, which is not ideal. Sound was as good as my Rotel RCD1080 CD player, and I sold the CD player.

Then I built an audio server based on Intel server motherboard (no bells and whistles), Xeon CPU, SSD for JRiver and Win Server 2012. Music on a HDD inside the PC. Fanless case, headless (meaning no monitor and video turned off within the PC). Big jump in audio quality, using same Audiophilleo and Metrum. I also had/have a linear power supply.

Next I added a Paul Pang USB card. Another improvement in sound.

Next I added AudioPhil's Audio Optimizer, which is a software that optimizes Windows setup. Huge improvement in sound. Totally unexpected!

Then I turned Windows Server to core mode. Another significant jump in sound quality. Then I added 3M RFI absorbing paper inside the PC, for another improvement.

The Audiophilleo is of course an asynch USB converter, and a very good one. This experience tells me there are definitely improvements to be had by focusing on the computer itself. Some are software based and can be done on laptops and desktops alike. Most hardware tweaks can be done on desktops only.

Thanks for all of the inputs. before I have had my laptop near my DAC PS audio Direct Stream on the audio rack, I now change the set up for convenience by having the laptop on a small stand right next to my chair. With that, I use a 25ft usb cable to connect laptop to dac. For this current set up, I have an option of buying/building a small form factor PC. It is a little bit cheaper and more powerful than laptop but I am not sure that Do I need all of that power on PC? or another option is to install window server on a PC instead of win7. I never try win server before so I really do not know it is better than win 7.

If you are only going to do playback (no DSP, convolution, etc), then you don't need much power - or RAM, for that matter. Especially if you use Win Server in core mode.

To me the most important thing is to avoid all posible RFI/EMI sources. Wi-fi within the PC, monitor, HDD, fan are all such sources. A small computer sitting by your DAC without a monitor, and controlled from an iPad or such is what I would recommend from a sound point of view. My PC is connected thru LAN to a wi-fi bridge, so all that electrical noise stays outside the computer.

Take a look at the CAPS servers over at computer audiophile website. I don't remember the names, but the least powerful machines would do, I think.

Mine is powerful but because I do DSP and plan to do digital crossovers, etc in there too.

I hope this helps