Limited Drive letters

XP Hom SP1, 384 M Ram, 1G Athlon. Installed new 120 G
HD. Partitioned into 2 ~20G partitions. appears to load
fine, but only provides letters for two partitions. Set-
up Primary HD in 4 partitions C-F,3.5 drive A, two CD
drives H&I, first two partitions on new drive show as
G&J. Changed all the drive letters on the CD's and new
drive. New drive follows G-L and CD's are M&N. Now
first four partitions show and no CDs. I think I've got
a limit set somewhere that is only allowing 9 drives to
show, maybe 10, but I have no B drive set. I remember in
3.1 and 95 there was a way to limit Windows from the
number of physical drives it would search when starting,
but I can't find a similar setting in XP Home SP1. New
drive is set as slave according to instructions. WD
(drive type) no help. Suggested changing cable
orientation, tried that too.
Thanks for the help
Ray