what are you wanting to do? if its just general day to day browsing and casual gaming onboard is fine, but if your editing or a serious gamers then go for a seperate card
At present i am using the Audigy zs platinum pro and will be having the Fatality professional along with the asus extreme motherboard so it was just a general enquiry to see if they have got better.
To be honest with you, if you intend to get a superior sound card to the onboard (personally I have never had any issues with my onboard, and I do alot of gaming) - make certain that your speakers & headset are also of decent quality.
Know what, the standard onboard sound that the Asus P6X58D-E comes with is great. I have a SB Titanium Fatal1ty Pro and I can't tell the difference if I'm honest lol.
Onboard Audio is getting better and is far better than it was a few years ago but it's still not up to the same standards of a dedicated sound card so if you want high quality audio, the I would recommend getting a SC or simply transfer the one you currently own into your new PC when you get it!
a long-time ago it was a advantage to have a sound card with its own processor so take extra load off the cpu, but those days are long gone and unless you are doing some major music production onboard is generally good enough, i run both just so i have team-speak on a separate device and its not sharing with the game which gets annoying
Got to agree, once spent a fair whack on a sound card and didnt notice a difference from the onboard sound I have now, other than a more fancy control panel for it