I did some reading on that DFI board, and a lot of people said they had trouble running 6800 cards on it. Granted these are only Newegg reviews, but ill post a few.
" mobo is great unless your trying to us it with a 6800 card. if you are plpanning on buying a 6800 get a different mobo"
" I really like this MoBo, one of the easiest to work with, but as the poster before me said, the nf3/geforce6800gt stuttering issue nearly drove me insane this week. Other than that I have no complaints about this board, and I would recommend to anyone with a different graphics card."
"http://forums.nvidia.com I'm very happy with the quality of the DFI lineup however I am afflicted by the Nforce 3/ Geforce 6800 stuttering and neither DFI nor Nvidia has a fix for it. Before buying into the Nforce lineup be sure to read everyone's problems with it at http://forums.nvidia.com
Is that something I need to worry about?