In recent experience I found that extra load makes a difference even on a high spec computer.
Cant explain it other than what my ears are telling me.
That said, I never did perscribe to the "its just 1s and 0's" camp though
Got curious, so I bought my work PC through to the lounge (Dual Xeon CPU, 32GB ram yada yada) and installed JRiver on it and set it up the same way I have my music server.
Heard the difference between switching Memory Play on and off, changing the buffering settings, anti virus&firewall on compared to off...
Task manager showed barely a blip, but ears said different.
I don't profess to have all the answers, just know that in my experience increased overhead on the system_DOES_make a difference.
Always a believer in experimenting and listening, and I found that it does makes a difference, even on a "high end" PC system.