new build computer wont power up.

[feletan]

I just bought many different pieces for a new Gaming computer
P8 H61-Mx LGA 1155 motherboard
GTX 750 TI GPU
i5-3470, 3.2 GHZ, ivy-bridge CPU
4GB's of Corsair vengeance Ram 1600 MHZ
1 TB hard drive
standard Sata Cd-rom.
and a 700W PSU

all brand new items all look intact and unbroken no bent pins or anything
I plug it all in correctly follow the manual but still the computer wont start up
there is a little green LED light that lights up on the bottom of the motherboard when the cable is plugged in to the PSU. iv'e also tried a 300W PSU and still the same thing happens, tried with and without the GPU plugged in as well as the ram, still the same thing happens, no fans start up either. I have no idea what it could possible be.

 

[feletan]

Never mind i figured it out, For anybody else who has this problem check that you have used the correct motherboard screws to elevate your motherboard a little bit above your case, turns out i was shorting me board and stopping it from starting up because it was touching the metal case.