The problem: I have a 17 Inch Intel-based iMac (2006). when I press the power button I can here and feel fans running but the Power Indicator Light turns on and the screen remains black. Nothing else happens. Not sure what I did. I didn't take anything apart. I checked over the whole compartment and all connectors appear to still be connected. What I did before it happened: I did some research figured out how to disassemble the IMac, purchased a new hard drive, backed up the computer and when I took it all apart there was a third connector on the hard drive (temp sensor?). The new drive did not have this connector so instead of experimenting I put the computer all back together. Any help or suggestions appreciated.