i'm not an ATI fan....so i wanted to stick with Nvidia .
Brand preference is not the way to go. You've got rid yourself of that mentality and take all brands into consideration to make the right purchase. Both the 4850 and the X38 are far better products than the competing 9800GTX and 780i.
But it's your money, so who am I to question your purchases? Do as you wish, I just wanted to give you a bit of friendly advice