Is the i7920 or i7950 better to over clock?? Also would it be smarter to start with 1 very good graphics card and save up for the second or buy 2 lower grade one's?? thanks every one I have $2,200.00 ready to buy!! So next is a 1200 Watt PSU over kill?? What is the best amount of DDR3 to start your build with.. Should I use Microsoft 7 premium or Ultimate??