Hello everyone. I am looking to replace my tired old 5770 with a GTX 680. Now what I have read in order the flash a 680 it needs to be a reference card, 2GB and also with dual 6 pin power, is this correct? If so what cards would be suitable for my machine, and is it a difficult process to flash a card. My Mac Pro is a 5,1 Quad. Thanks and appreciate the help. James.