EIDE connector port problem

Hello,

After opening my computer's case to change the CD-burner I'm experiencing kind of a strange problem. I have two CD drives and they both were on the secondary EIDE channel. I also have 2 hard drives and they both were on the primary EIDE channel.

The problem that I have now is that whatever EIDE ribbon I plug into the primary EIDE connector (the port on the motherboard), when I start the computer the drive that's connected on the middle of that ribbon (not the drive that's connected on the end of that ribbon) is not recognized. If I plug the ribbon with the two hard drives, the hard drive near the EIDE connector on the ribbon is not recognized. If I plug the ribbon with the two cd drives, the cd drive near the EIDE connector on the ribbon is not recognized. But if f I plug either ribbon on the other (secondary) EIDE connector, both drives on that ribbon are recognized fine. All the drives (hard and cd) are jumpered cable select. I'm fairly confident I didn't do anything on the primary EIDE channel which gives me the problem now. I was working with the cd drives that were on the secondary EIDE channel.

Any ideas on what's going on here?

The computer is a XPRS400-1000. OS is windows 2000.

Thanks Jim