Unrecognized HDD

Ok guys, I just joined and I'm needing help on a weird occurence on XP.
I have 2HDD as well as 1 Sony DVD drive installed.
Originally a 20GB Maxtor droive was set as Primary master, a 120GB Maxtor as Primary slave and the SONY DVD Drive as secondary slave.
I was having problems w/throughput on my D: Drive (Primary Slave 120GB) so I decided to move it to secondary master to see if the throughput would improve.
When I boot the PC, BIOS recognizes all the drives properly, however XP only shows the 20GB drive as C:, and the Sony DVD as D:. I have no idea what happened to my 120GB drive. I am sure the jumper settings are correct on all 3 drives. I am using XP home. The C: drive(primary master) is FAT32, the unrecognized drive (secondary master)is NTFS.
Please help, I've been building PC's for years and have not had as many problems w/XP as with all other OS' combined, and I include OS/2.
Thanks
Mike
Cowboys-fan

 

When you go into Computer Manager and click on Disk Management, does the drive display in the list at the bottom of the right side? If so, it may be as easy as assigning a drive letter to it again. If your Sony is showing up as D, you probably want to change the sony to E and make the 120GB your D.

 

Unrecognized Drive

Thanks a bunch GusD. I didn't check back until now. In the meantime, I was so enraged with XP that I went ahead and performed a fresh reload.
Needless to say, the drives show up now.
Thanks for your help anyway, I really appreciate you taking your time to respond.

Mike