I'm more than confident that 1000w is enough.
Can't believe I forgot to put down what OS I am using. I'm on windows 7.
I have looked into this alot further since posting and it seems with this board, and windows 7, mining like this should be no problem at all as long as I use a dummy VGA connector in the cards I am mining with. I think there may be ways to do it without a dummy connector but for now the most reliable way seems to be using one.
Since posting I have purchased a sandy bridge system but as far as I am aware everything should still work fine. The only problem I forsee is with the new board I have and its PCIe lanes.
Its an Asus z68 pro and has 1x PCIe x16, 1x PCIe x8 and 1x PCIe x4 (I think this is tied to the USB 3.0 and something else but they are not something I will be using). I'm a little worried about A) If the card will work in the PCIe x4 slot and B) if it does work, how will this effect the performance for mining. From what I read difference for mining would negligable but I haven't really found any solid proof.