Your build looks great! lots of quality parts there. 650 watts if fine for your system even with a mild overclock. I'm more partial to corsair or antec units below the 1000w range and would suggest 750w. I'm not sure how much the coolermaster unit you are looking at costs in your area but look it to comparing it vs 750w and other brands. If budget is an issue go for DDR3-1600. You won't see much difference in 1600 vs 1866 for day to day gaming and video editing on that setup. More psu just gives you a larger upgrade path should you chose to upgrade or add another video card.
Praetor» i7 990X 3101A239
» Asus Rampage III Black Edition
» Asus GTX 470 & 570 Tri-SLI or Three Sapphire 5850's CFX
» 6GB Corsair Dominator GT TR3X6G1866C7GTF
» Corsiar Force Series 180GB
» CORSAIR Professional Series AX1200 1200W
» Microcool Banchetto 101
Defiant» G74SX » 16GB ram » Corsiar Force Series 180GB » 750GB Seagate » Blu-ray