I'm not really sure I understand your question. I am reading it that you are asking how to get the video and monitor to display something, or beep to give you an error you can do something with. If this is wrong, please try and rephrase the question if you can
There are a few things to try. Isolation is your friend. Firstly try a different monitor (if available) or try the monitor on another machine. If it's working fine, then move on. Try turning the video off on the motherboard, and plug in any video card (that you know works), and see if you get something on there. Make sure your monitor is fine though, or you wont be able to tell. By doing this, you have isolated both the monitor, and non-onboard video.
Most motherboards beep once if everything is fine, right around POST (some before some after). If your machine isn't beeping at all, it could mean a problem. (probably an error it doesn't have a beep code for though).
Other things to try (independantly, to make sure you know what fixes the problem):
Ram (Different ram and/or different slot)
Power Supply (Different P/S and/or that P/S in another system)
Another thing to do is take out EVERY card, and unplug EVERY cable (including HDD, FDD, Sound) so the machine only has enough parts to boot. I have in the past seen a faulty cable stop a machine from booting. It actually did exactly what is happening to you.
If you still get no joy, your motherboard is probably busted in some fashion. See about getting a warranty, and if you documented your fault finding path (it's a good idea) you can give that to the people you are getting a warranty through, usually speeding up the process of you getting a new one.
Hope this helps.