I'm trying to crossfire my 2 HD7950. I have a gs600 psu. It only has 2 gpu plugs going to it and it requires both to even show me a display from the 1st gpu. With only one plugged in to the 1st gpu there is no display and a beep when I start the computer. However, the 2nd gpu fans still run when the 2 plugs are on the first gpu. I still cannot seem to get my computer to find the second gpu and the amd settings will not show the crossfire option to enable it. Do I need to get another psu that has more the 2 pci plugs in order to run power from the psu or is there a way around this? Cause if the fans are running it's obviously getting power from the motherboard.