I would reset the CMOS. Remove the battery on the motherboard, it may look like a watch battery. Unplug the computer and push the power button, that way it drains any power that is in the capacitors on the motherboard. Then remove the battery and let it sit for about 10 seconds. Reinstall the battery, plug the computer in and restart.
It could be a bad cable, but if the problem presented itself before you moved anything then the chance of a bad cable is small at best. It could be the IDE controller on the MB, that would give the type of error you are talking about.
93 Black Mustang GT