Alright, well, I got the power working with every part inside the case. There are a few weird things though. A, one of my fans won't start to spin unless I give it a very light tap, then it spins infinitely. Secondly, as I thought I finally fixed my computer, I plugged it into my monitor and it still did not work. All the lights on the mobo come on, although they turn off after about a minute. It SOUNDS like a working computer. The disc drive even popped open when I pushed its button.
You see here you stated the mainboard lights go out then when this happens your computer isn't running even if the fans are turning. it isn't booting or anything.
I've built Alot of computers in 15 years and never have I seen the mainboard leds go out unless it wasn't working. So no matter what you think, if these leds are all off it will not run.
Im sure others here will tell you the same thing, not just my opinion. If you asked someone here to troubleshoot this they would take it all apart start from scratch and build it one part at a time until the problem is found. Even new parts can be bad don't assume it couldn't be something bad. my 2 cents worth