I Bought an new A-Open HQ-45 Pro / 250w case with a psu yesterday. After spending a couple of hours taking my old rack apart and installing a mobo and all the other necessary stuff to this new case, I find out that the PSU doesn't work! I don't know what is wrong with it, but when I put the powercord in to it and flip the power switch nothing happens. The fan doesn't start moving and I can't hear the slightest sign of a hum. Now, what should I do? Do I just simply go back to the store and say it's busted or is there something else I can try to fix the problem?