CompuServe Messages

I have an Adaptec 1542b SCSI card running with an IDE drive card and a 1.3 gig SCSI hard disk on a 486 50. I've told setup that I don't have any hard disk so that the Adaptec card will control the drive. My problem is that when booting I get two 1.3 gig drives reported, one at address ID 0 and one at 1. There's only the one drive in the system. When I do a dir command both drives list identical files. If I save a file to one disk, it appears on both. Obviously it's the same drive being found twice and the system doesn't know it but I don't know where the glitch happens. Any suggestions? Jerry