Got a similar situation. Bought myself a new asus p5q motherboard. Put all my hardware on it (2 x 1gb ocz memory, intel core 2 duo e6300 cpu, innovision gf 8600gt, psu spire 420W) and computer doesn't boot (fans spinning, no beeps, black screen). Actually, it may boot 1 time from about 5-10 tries. If it boots, it works just great. I tried removing videocard, cpu and ram - in every case speaker gives specific beeps that a component is missing.
If i put my hardware on the old mobo (msi 945p neo3-f) it boots ok. So I decided to take the new p5q to the service-center. They put their hardware on it (their p4 processor, their 512mb ram, their PSU and my video card). And it boots perfect!