I just found out about this. I found a bunch of threads all over the internet explaining how to install Creative X-Fi bundled software to be used with a Realtek on board HDA. People who did this report significant improvement in sound quality. I decided to try this mod and found it to be true. I have experienced improvement in quality, plus the audio output became much louder.
Here are some more threads I found on the topic:
If anyone is willing to put it to the test, I'll be more than glad to read about your experience with this mod.