Hi,
I admit it is difficult to tell on youtube if there is much difference. However one thing I have found over the years relating to digital audio on computers is that a lot of the audio quality has more to do with how a sound chip is implemented on a system and whether or not it is filtering out external noise rather then the actual chipset used.
A lot of times I've found that onboard chipsets pick up a lot more noise from the system resulting in lower quailty audio then actual audio cards. I recall a few years back when I did an experiment - I had a MB with an onboard chipset (c-media based) and a PCI sound card using the same c-media chip. When I plugged the PCI card into the MB (and disabled the onboard audio) the audio quality was significantly better then when using the onboard - and it used the same driver.
However on the other hand I've also found that some low-quailty PCI audio cards have a habit of picking up external noise too - producing low-quality audio. A lot of times it has more to do with the circuit design on the card and quality of the components rather then the chipset or driver itself.
