Does the PSU fan spin when you hit the power button? If everything is plugged in right there may be something else dead on the board. The 8 pin in the 4 shouldn't effect it as they are designed so you cant plug the wrong half of it in. Only thing I can really say is make sure that everything is plugged in right.
Doesn't spin, though there's a quiet rhythmic clicking inside when I have it plugged in. Double-checked and everything is plugged in correctly.
The CPU may be burned out like I said before, but that doesn't matter to me until I can turn the thing on, and right now, there's not even power going to the mobo.
Even though the other PSU without the auxiliary plug gave off a charge.