New Corsair PSU not working

I just got a Corsair GS700 PSU for myself and have a big problem, after connecting all cables(verified thrice) when i hit the cpu power button nothing happens, as in no fans spin no led lights nothing just the way it is when it is switched off, so to deduce what the problem was I used a paper pin and put one end in the green wire slot of my 24pin mobo power cable and the other end in one of the black slot just like in this vid http://www.youtube.com/watch?v=5FWXgQSokF4 after turning on the power switch of my PSU, for just a split second the blue LED light came and went off and the PSU fan took approx. just a quarter round basically hardly moved. So what is causing this and is it repairable or do i need to replace it? please reply ASAP, and so I dont think there is any problem with any of my CPU components, I yet haven't tried to switch it on using my previous power supply, and anything you feel might cause the problem please feel free to state it.