IDE HDD Problem

IDE HDD : Seagate(ST38421A) 8.4GB
OS : Win9x/2K/RH Linux 6.0
Problem :
When i am installing this HDD(with FDISK),it shows 8221MB and after formatiing it in FAT32 its showing 2.52GB used space,rest is free space,whereas i had not installed anything on to it.
I had tried the track 0 script usinf DOS debug command,but in vain
also tried partition magic 6.0,but no required results,I had used FAT16 formatting also,but it had not worked.
i am loosing a space of 2.5gb out of 8.4gb IDE HDD
pls help