So here's the deal. I have 3 400 GB sata drives in the computer. Eventually I'll get an adapter for 5.25 inch bay to add a fourth to the comp itself, but for now I have an external sata enclosure. The enclosure can hold up to 4 drives and connects via eSATA to a raid card (silicon image). I had one drive in the enclosure, and it all worked fine with drives installed as sda to sdd. However, when I add a second drive to the enclosure, rather than add sde, it adds it as sdc and does not show the other drive that was sdc. Running FC4 running from hda (IDE) and optical drives on hdc and hdd. What do I do?

Btw, the new drive is a WD and the same model as at least one, maybe two, of the other drives.