wow that high resolution picture x) was hoping to see the connections but guess that is out of the question lol
and yes, the embedded power button should work. What you can try to do is test the 12V pins of the main PSU cable, with the paper clip method. check it out here:
https://www.youtube.com/watch?v=ixcWCrYpw3Y
(also, you have the fan on your Hyper 212 EVO on the wrong side. It works better when it is pushing air against the cooler, towards the back of the case, where the air exhausts)
but this last part is just a detail. lets try to turn the rig on first