Sorry ... this may not be much help ... but I had the same problem recently with an ASUS board. CPU fan and other fans would spin, the LED on the board would light, but there was no video, no beeps, and no responsiveness to the power button on the case. Even tried shorting out the board pins using a screwdriver -- to see if the case power button had gone bad. Still, nothing. Tried other video cards that I knew worked -- still nothing. Tried the memory sticks in another machine -- OK.
While it COULD be a PSU problem, I replaced the one in my ASUS system with a new one that I knew worked in another PC -- and still no display or beeps. So, a new PSU is unlikely to fix it.
Had to end up replacing the board. You might have to look into RMA-ing the board.