I have the same problem with the same CPU, RAM, and similar motherboard (GA-Z68XP-UD3). I bought everything from Direct Canada, a sister company of NCIX (pretty much the same company, just different storefronts). Perhaps they received some bad stock from Gigabyte, who knows.
EDIT: I decided to check the CPU socket. It turns out it was 1 (read: ONE) pin that was off by mere microns, JUST barely noticeable to the naked eye. For some reason, it was shinier than the other pins - I probably wouldn't have been able to notice it if it wasn't. I was able to gently nudge it back into place. I knew how delicate these pins were the minute I lifted the plastic cover for the first time, so I know for a fact that I installed the CPU *very* gingerly. Thus, I'm reasonably certain that the socket arrived like that. It also appears to me that a majority of people with this exact problem have Gigabyte motherboards; perhaps Gigabyte needs to enforce better quality control on their CPU sockets. Of course, it's certainly possible that the bent pin was of my own doing, but considering that it was ONE bent pin, somehow shinier than the other pins, and that the socket was exposed for all of maybe thirty seconds before I gently put the CPU on top of it, I find this unlikely.