I don't know if it is peculiar to the latest nForce motherboards but mine has never beeped on start up - not even the single beep on start up, I tried speaker connections etc and even started a thread on this forum. However my system did boot up fine and works well.
Have you tried checking the memory as that is often the cause of boot up failures? If you have two sticks try them one at a time and also in different slots.
Does the CPU fan spin, and the power supply fan and any other case fans? That will give some indication as to whether the PSU itself is getting and delivering power to the board.