What your describing sounds physical. Is the 200gb new? Could it be the drive is bad? If not, I'd try doing a format, a low level format if possible. See if that does the trick... Before you try that though swap the IDE cable, I've had luck with it. Also, try playing with the jumpers, sounds strange I know, but I've had drives act funky, then I change the jumper from "master/slave" to "cable select" or a different "master/slave" jumper config and issues disapear.