Install only the power supply, processor, one hard drive, one CD drive, the floppy, the video card, and one stick of ram. This is pretty much all you'll need to get it up and running.
The reason why I recommend this is so that it makes things easier to trouble shoot. If everything works fine, then start added other accessories one at a time, to see if they all cooperate with each other.
Oh and it will take a long time and lots of rebooting.