with xfx 650w u have a good quality modular psu... and u have the sufficient wattage to sli... i would change the wd black for samsung spinpoint f3.. its faster and cheaper..
also.. why do you need 2gb?? get a normal one... and its not gts its gtx
noctua its very ecpensive... why dont u get cooler master hyper 212 plus... its much cheaper and it does the job fine...
haf x its very expensive... haf 912 makes a good job and its much cheaper