having trouble with asus crosshair motherboard, or possibly the problem lies with the amd 64 5600 i have paired with it.... i dont know. anyway when i try to power up, it will only stay on for about 3-4 seconds then shuts itself off... ive tried several different power supplies and still cannot figure out what the problem is. it also does this with or without the video card and ram in it too... i usually power down my pc normally then i would also shut off the switch on the back of the power supply. this all began after leaving the power supply on for a couple days... can anyone help!!!!