Message-ID: <32EF3A32.101A@eik.bme.hu>
Date: Wed, 29 Jan 1997 12:53:22 +0100
From: "DR. Andras Solyom" <solyom AT eik DOT bme DOT hu>
Reply-To: solyom AT eik DOT bme DOT hu
Organization: Technical University of Budapest
MIME-Version: 1.0
To: djgpp AT delorie DOT com
Subject: Re: 400 MB of my HD is missing
References: <Pine DOT SUN DOT 3 DOT 95 DOT 970128161942 DOT 26911B-100000 AT ernie DOT eecs DOT uic DOT edu>
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The reason lies in Dos's 16 bit FAT system. You can have less than 65535
units (called clusters) on the HD. So the bigger a HD gets the bigger
will be the clusters. On the other hand, sector size is 512 bytes in all
these cases. Here is a simple table:

HD Size     Minimum required cluster size       Space wasted (%),
average
 Mbytes           (sectors/kbytes)
16-127 Mb         4/2                              2
128-255           8/4                              4
256-511          16/8                             10
512-1023         32/16                            25
1024-2048        64/32                            40

If you use Norton's FS (file size) command you can find out that those
400 Mbytes are wasted, because every file must occupy at least one
cluster, even when that cluster stores only 1 data byte. Try to
repartition your disk (you can do it without loosing any data with e.g.
PartitionMagic from Powerquest. I bought it and use it succesfully).

					Andras