Well... thats two mobos now that have been destroyed.

I convinced Dell that the video card is bad and screwing up the mobo and they are sending me a new video card, mobo and processor. Last time I try that. And I even read the technical specifications BEFORE I just started plugging in parts.

My Boss says: "Remember when you were a kid and you had all those toys? You were one of the kids that tried to put the triangle block in the circle hole with the hammer... weren't you?"

I swear I researched and thought I understood it.
So, I've come to the conclusion that the Dell Dimension 8400 sucks ass.