I put together a computer with an nf3 chipset and a athlon 64 3500, I used the hard disk from my old computer and made another partition to install the new one and then moved the documents I needed to the new partition. Everything is fine except that when I reboot the computer it logs off from windows then the screen goes black and the monitor led starts flashing as if it was not connected to the cpu. The computer keeps running but nothing happens,I have to press the reset botton on the computer case to restart. What can be the cause fo this? could it be that I have two installations of windows?