Why does upsampling make a difference on cheap soundcards?

[yepimonfire]

I've noticed on most of the on board realtek sound cards commonly found in laptops and desktop changing the sampling rate from 44100 to 192000 improves the quality of the sound,regardless of the original sample rate of the media, however, using a FiiO usb DAC or connecting my laptop to my onkyo receiver via HDMI it doesn't matter if I upsample it or not, it sounds the same. Why would this be?

 

[fmw]

It is impossible to get better sound by upsampling. You can look for a scientifically valid reason that it would, but you won't find one since it doesn't. A computer has no way to know what bits of information were removed from the original recording. All it can do is add zeros and make the file size bigger.