I had to disassemble a 20" iMac due to HD failure, found out that the S-ATA controller is gone so I removed the drive to recover the data and mounted it all back, thought of attaching an external FW drive to install the operating system and keep using it as a backup machine or file server, by the way, mount it back, four cables behind the screen, the video cable on the board (a big one you can not mount any different than correct) and the screen temperature sensor that also is one way plug, after booting up I realized that the screen is blurry, what might have happened???