are you going to be playing games?
That's a big question cause it will make a big diffrence. If no... go on ebay and get a Diamond Monster MX400 sound card... less than $15 and just about every OS I've used will see it and it's just a great all around card. They don't make em anymore but I've got at least 5 of them and have, honestly, had NO problems with them. I even have a hard time breaking the drivers, windows knows this card like it was designed for it 110%. I have a Creative Audigy and have occasional problems. I'm really thinking about replacing it with a good ole MX400. Unless you really need a specific function of a certian sound card... go with the MX400, it's such a solid sound card. Sound is awesome and ease of use.... simply could not be better.
MB and CPU.... I'm an Abit/Intel fan myself. I've been using both for years and have had very little problems. They will be a bit more expensive... but I say it's worth it.
I don't want this to be a Intel vs AMD thread... either one will get 90% of what you want done quickly and easily. I prefer Intel, have had less problems with them and have had a bad history with AMD. So I'm partial to Intel.
edit: MX400 BuyItNow for $8.
http://cgi.ebay.com/ws/eBayISAPI.dll...sPageName=WDVW