Second Hard Drive Recognition Problem

I have an Athlon 750 computer with Win 98 SE; I have set up a WD 20 gig HD as primary master and a WD 8 gig as primary slave. They are both connected to the primary IDE data cable; during boot up both drives show up on the screen and in the CMOS. When I am in Windows C drive shows up as 20 gig and D drive also shows up as 20 gig. When I go to dos prompt both C & D drive are 20 gig. Need help in figuring out why the 8 gig HD does not show up in Windows. Any ideas would be appreciated.