when i turn the sysem on the power light goes on for about 5 to 10 seconds then it shuts off the cd drive lights up the cpu fan spins the green power light is on in on the motherboard but then everything shuts off exept the green light it has a amd 2000+ xp cpu on the asus a7s333 i have re seated the cpu the fan and the memory many times but still nothing happends