HP or Dell for computer listening ?

Well that’s what Jplay said 8 years ago, not Darko. It can shut down some processes, just like Audiophile Optimizer does, and does have some positive effects, but does not eliminate jitter. Its effects are related to the OS, not the hardware, where most of the problems originate. Software can not make up for low quality or poorly designed cables, drives, USB circuits etc that induce jitter. That’s not how it works. I’ve built plenty of servers and own Jplay and other software. A system capable of high resolution is needed to hear any differences anyway, so listening to Youtube on a cheap desktop computer makes it a moot point.

Apple Mini with Channel d's Pure Music.

I currently have three Dells all of which work fine after I did one important thing. I guess this would be true with all sound cards by the way with other brands. Go to the realtek website and download their free high definition driver file. Some 240mb last time I did it. Load that on your PC and it makes a TON of difference. What comes factory loaded on your PC is real junk by comparison. Also if using a laptop make sure the speaker size setting is set to match what you have. In my case large and it also made a difference. Make sure you test to see you have your left right channels correct also as they can be easy to mix up. Headphone won't matter of course but you will hook speakers up sooner or later too.