personally building my current computer i recieved a bum AMD cpu AND a fried mobo (gigabyte). But i had purchased both from
www.ncix.com, and i returned them within their grace period and recieved brand new parts... along with a nice bonus for my trouble. Both new parts work absolutly wonderfully, my motherboard came with an auto bus detect, or as i chose to do, set it manually for the inevitable overclocking.
Basicaly:
they wrap the parts in plastic... plastic can conduct static... i think you see where i'm going with this... bad parts out of the box can happen, so test them fast and get your replacements.