Hard Drive Issue

I recently bought a used IBM NetVista office machine with a bad motherboard. I upgraded the motherboard and discovered the machine had an additional hard drive installed. After loading the OS Win98SE it now shows a 3rd drive. It made no sense to me, so I downloaded and ran Belarc Advisor and got confusing results:

Drives:

36.36 Gigabytes Usable Hard Drive Capacity
34.66 Gigabytes Hard Drive Free Space

LG CD-ROM CRD-8481B
Generic floppy disk drive (3.5")

IBM-DTLA -307020 [Hard drive] (13.13 GB) -- drive 1, rev TX3I
QUANTUM FIREBALLlct1 [Hard drive] (10.10 GB) -- drive 0, rev A01.

Local Drive Volumes:

c: (FAT32 on drive 0) 10.10 GB 8.40 GB free
d: (FAT32 on drive N) 13.13 GB 13.13 GB free
e: (FAT32 on drive 1) 13.13 GB 13.13 GB free

How could I have a total of 36.36GB when both drives installed combined should only have 23.23GB total? I also get a message under system properties under the performance tab.

"Drive D is using MS-DOS compatibility mode file system"

Do I need to locate and updated driver for the IBM HD? If so, would this correct the false storage capacity information?


Any help on this issue would be appreciated. Thanks!