Which 7850

[gamingpcplz]

THere are so many 7850's out there
some are OC'd slightly some now but I am looking for the one with best cooling and best performance

currently im seeing the msi twin frozr which is at 900mhz and i want to OC any card i get to about 975-1ghz

So im asking you which one is better For oc and performance and cooling

 

[gamingpcplz]

how much would this card thrortle to on 16x/4x if i wanted to go crossfire