Hi Chris just reading through your posts, You mention that you have been trying to get another drive to work,
Can you tell us if it is still in the pc and connected and whether you have checked that all the cables are in place, and I'm a little concerned that you may have solved one problem but caused another
if you have been swapping cables about have you bent any of the pins on the connectors,
also if you have a spare or another pc have you tried the drive in that one to see if it is a drive problem?