Might be motherboard, would be great to see a photo of the motherboard with it's connections to make sure all is connected well. If you want to could you make some photo's of different parts of the motherboard and upload them to imgur, but that is up to you.
You can use Imgur to post a picture here,use the "img" link.
Click "new post" ->choose "upload images" -> "browse" ->choose the picture and click "open" ->put cursor on the picture that you uploaded->choose "share links" and copy the img link,paste it in your next post.
yes, i had left all the origional EVGA cables plugged into my mobo so my wire management in the back would be intact lol so none of the wires were moved or unplugged from the mobo. i also just tried shorting the power on prongs on my mobo and still wont power on. could mobo be the issue?
Other option is breadboarding, take the motherboard out of the case, put it on the box it came in and only use cpu+gpu+one stick of ram in second slot from the cpu out, again try to start by shorting the front i/o pins for that.