Recently I had a ECS K7AMA mobo do very similar things all my other components worked though so I was pretty sure it was the motherboard. It would turn on all fans but no video, and it wouldn't turn off for some reason only on. Anyway I ended up replacing it with a newer Albatron board and everything was fine, but be carefull as with a new motherboard my hard drive didnt like it so I had to format the drive and lost everything on it.