I am building a PC. I have a monster power supply at 700 watts. I would like to get an amd card for gaming. I play minecraft. I also want it to be crossfire. I want to do crossfire. My budget for 2 video cards is about $120 but I can raise it a little. Which card should i get. I play minecraft and also do video editing. I also want to play online games. I am also interested in topping the GT 640. Which card should I get?