I have a computer with 3 hd and a burner. I have it set up so that 2 hd are on one cable and a hd and the burner are on the other. Problem is that the secondary IDE won't detect both the hd and the burner. It will detect one or the other, or neither. If they are both plugged in (hd master, cdrw slave) neither drive shows up. If the cdrw is master and hd slave then the cdrw shows up but not the hd. And if one or the other is plugged in it will detect which ever is plugged in. Why won't it detect both drives...? I have checked and rechecked to make sure they are in the proper order and the jumpers match.

For troubleshooting purposes -

1.Try setting them both to cable select,and see what happens.

2.Disconnect any Floppy or even Zip drive(unlikely)

3.Try swapping the HD on the second chanel,with one on the first

4.Try disconnecting one of the drives on the Primary IDE

5.Try a new IDE cable

6.Complain nothing works.

did you try Cable Select in the BIOS?

You didnt mention it but does your mobo support SATA? I have seen what you are describing happen when a board that supports SATA has both PATA and SATA enabled in the bios. if the board supports SATA but yu have no SATA drives installed then check the bios and if both PATA and SATA are enabled switch it to just having PATA enabled.