From what you say, it sounds like the motherboard and CPU are active.
You probably have bad/incompatible memory or scrambled BIOS settings.
On motherboards with integrated video the memory is shared between video and CPU. (Yes, there's a performance hit) The first thing to get control of your system during boot is video... this happens before the POST can test memory and give you the SOS beep code for 64k failure and the video bios can't hook up to ram, so you end up with no display.
First, turn off AC power at the back of the machine, remove all but 1 memory strip, hold down the END key above the up arrow on your keyboard while you turn the power back on. On motherboards that support it (If memory serves, Intel does) this should bypass all POST tests, reset the bios to "safe values" and take you into the setup screen where you can hopefully configure for the memory you have installed.
IF that doesn't work... try swapping in different memory modules. It's possible you've got a bad one.
--->It ain't better if it don't work<---