I've pretty much narrowed down my selection to this board, but want to be as certain as I can that it will be compatible. These are the expansion slots it's got.
2 x PCI-E x16 (blue @ x16 mode, black @ x4 or x1 mode)
2 x PCI-E x1
3 x PCI

My 8800 video card will take two slots. I have a sound card but I could also choose to use the on board AD1988B 8-channel High Definition Audio CODEC which is better than most on board audio. Other than that the only slots that would be occupied would be for the NX and the daughter card. The board has the Intel Chipset, and this board is very highly rated for quality components and stability. I'll be running a quad core 2.6 extreme, and 2 gigs of DDR3 1600. It'll have a 75GB Raptor system drive, a 300GB drive for applications, photos, music, downloads, etc, and I have an external 1TB GSata thats two 500GB drives in software raid that'll be for video editing.

I don't really see any issues. I'm a little worried about this video card and the overlay, but if worse comes to worse my son will have one **** of a game card and I'll have to get something that's proven to work. Everyone seems to think this card will work but I haven't found anyone yet whose actually using it with NX Express for overlay.