Chosen Solution
Trying to save this one for a kid. Even with the CCFL out it is usable. Plulled the HD (it had been upgraded to 2TB), wiped the drive and installed a clean system of El Capitan on a MacPro. The Pro (2008) runs fine using the drive as an external, Booting iMac from an external enclosure, Machine boots fine in Safe Mode but not standard mode. (I get a multicolored dotted display with a black box. Does anyone know what to pull out of the library to get it not to check the display so it can be used again. @danj
I think your facing a SATA I/O issue here the ST2000DM001 is a SATA III (6.0 Gb/s) drive, this system only offers a SATA II (3.0 Gb/s) interface. Depending on which version you will have either a ATI Radeon HD 4670 or Radeon HD 4850 GPU, but when you are running in Safe Mode this series uses the Intel EFI driver in compatibility mode. with is why it works in safe mode. Try a known SATA II drive to see what it does.
