Hi, I just bought a second hand Mac Pro 1,1 with the ATI 5770 video card. I proudly installed it on my desk only to "hear" it. It's not as quiet as I had hoped. Trying to find out where the noise is coming from, I'm un the impression that it's the superdrive compartment. What's in there? All fans are running between 500 and 600 so I don't think it's that. Any ideas where this is coming from? It's a hum... Thanks.