Welcome to the forums mmstick!

Man, I wish I was that lucky that newegg would accidentally send me an AM3 board and PSU... that is a once in a lifetime thing...lol.
You got quite the big machines there. I can't even look at the X6's yet, the price tags are beyond my possibilities. But I got it in my mind to upgrade my X3 someday, and I've already checked that with a bios upgrade the board will be compatible, so now it's just waiting for the right timing for it.

Make yourself at home, don't be shy, and post if you got any questions or doubts, or if anything comes to mind that you would like to share.
And as always, keep on crunching!