What kind of power supply's were you using? Also list your detailed specs.
To me their's 2 things it sounds like could be happening. 1: You are missing a power connector, probolly a 4 pin molex on your motherboard.
2: It's Asus, the crappiest motherboard's for their price. Their new AMD boards are heavily flawed, even my A8V decides, shall we POST this time or not