Well now ....from experience i can say this....
I had Amazing sound in Skyrim...perfect positional Audio, great bass , all sounds Loud and clear, Till last weekend I updated my motherboard and LOST the ability to have my discreet (real) sound card. New motherboard does not have even one pci slot all i have now are PCI-e slots..grrr SO for now i have to use the on-board sound.
I cant believe how bad this really is. It svcks so bad it is not funny. its not the game...I have heard what the game can really do, this onboard crap is ...way to Quiet, sounds scratchy, tinny. NO life, no body , NO ASS .
I will fix this ...this weekend i will get a new sound card(looking at a Xonar Essence STX) and already know it will sound great again. But i really do feel for anyone listening to this garbage called ON_BOARD sound.
I tried the ROG drivers for the audio, the Realtec ones. all crap, tried Optical on the Board (much better then the direct 6 channel) but still crap. Truth be told ..I AM an Audio snob .

so this could sound ok to many but not me. The Optical was much improved ..but again Still crap....
New board is Maximus IV Extream-Z I7 2600 @ 4.8. Great board ..no PCI slot so i don't get to use my ASUS Xonar D2..

Was one of those moments dident realize this till i had the card IN my hand and looked down at the board and thought (forced obsolete).
And so as always in these threads...Thank you Bethesda for the Great sound in the game. Please don't break it.