Why have you ruled your PSU out of the equation, just because the mobo has a light doesnt mean the PSU is working properly, only that the +5VSB is working. If your PSU is making a very high pitched noise your PSU is most likely fried.
The best test that you can do right now without another graphics card is:
Pull the Power Cable.
Disconnect all drives.
Leave the power cable out for 10 minutes (some mobos are a bit funny about starting up in these kinds of circumstances).
Turn the PC on, it should spin the fans, and then the num-lock, caps-lock and scroll-lock keys should all flash at the same time just once (you might get bleeps, ignore them), try pressing the caps-lock key a few times if the light goes on/off your mobo is probably OK.
If the system does not start, do the same thing, AND this time take your graphics card out.
If the system does not start its either your PSU or mobo (and could be your graphics card as well).
Let me know how you get on.
Main PC, P180, CM Silent Pro 500M, i5 3570k @ 4.2Ghz, 8-GB @ 2,000MHz, 256 GB Samsung 830, 500-GB 7K500, MSI 660Ti Twin Frozr, PC is super quiet :o
Server, 6-TB RAID-5 array, + 2 x 2-TB backup drives, 380W Enermax Pro82+, 4x very quiet fans, positive pressure only, no exhaust fans
Living Room PC, 3500+, 2-GB RAM, HD501LJ