Windows 7: What do the Realtek HD audio drivers actually do?

Apart from the manager where you can manage your connection is there any stability or sound quality improvement. It definately fixes my Unreal engine 3 BSOD's, but why could that be?

I find it very very helpful!
I makes the sound so much better in my opinion.

Because you can set the EQ, to rock, pop, powerful, ect.

I have it set on "Powerful"
Theres a huge sound difference from having the EQ off, and having it set on powerful