Once you flip the switch on the PSU, nothing happens - except some lights my come on on some boards, just like yours. Did you check the board's connections to the front panel? If you installed the small 2-pin power switch connector the wrong way, it won't start.
It's very difficult to troubleshoot a system without a speaker and spare parts.
Re-seat everything, all power cable, video cards, pci cards, then try booting with one stick of ram (Remove one and leave one in the first slot on your motherboard).
A common problem with OCZ ram is that it is not getting to correct voltage for your computer to boot properly. If you use one stick of ram you can usually boot enough to get into the BIOS to set the ram voltage, after that shut down and put the second stick back in and you should be good.