Damn guys, just came back to this! Do you really think they were having me on?
And in which case, it could've been WHICH connector exactly that I had gotten wrong?
That sucks, cost me a lot more to take it to them.
Edit: Sucks hard. Really wish I knew some of you guys in real life. Do any of ya'll live in London?! In the future I'd much rather have my PC looked at by people such as yourselves.
And sorry for the super late response. I intend to put pics up soon!
Thanks again for helping me build a great PC!