Will the onboard video run though when the motherboard doesn't support it? No DVI, VGA, or HDMI ports on the motherboard. I'll try the other steps though. I may take it completely out of the case, set it up on cardboard and test it.
You need a port to connect to... odd motherboard has no ports at all to connect video.
If thats the case then you have to use a separate graphic card. I would try two different ones if one isn't working... make sure if it needs power that's plugged in.