Windows Installation Question

When I was over a colleague’s home the other day he was reformatting his pc. He has one hard drive and I noticed that it has a small unpartitioned space that I can’t make out if it says 0 or 8MB.

What exactly is that for? Can those spaces be used for personal data? Or is this some mad bug that comes with Windows?

If its unpartitioned then you should be able to extend and partitions, to the left of it in disc management, into the space.

On my system i have a 100mb system reserved partition before my C drive which is created at installation.

In the event of a harddisk with no primary partition, the first cylinder (cylinder 0, track 0) is for the MBR, while the extended partition is made of the EBR (track 0 of cylinder 1).

In these conditions, assuming that the harddisk classically has 63 sectors per track and 255 tracks per cylinder, the free space of the first logical partition only starts after:

MBR+EBR=whole cylinder 0+track 0 of cylinder 1=(255 x 512 x 63)+(512 x 63)
=8225280+32256=8257536 bytes=7.8 MB

And you can’t get rid of this 7.8 MB space, foreved wasted.

what the hell?

dang! does all windows based pc have this? i had reformatted my pc some months ago but i don’t recall having that wasted space which is why when i saw it while my friend was reformatting his i was like whoa!!! then again i wasn’t really paying much attention.

This “wasted” space (hmm, not going to make a riot for 7.8 MB?) is said to be seen “sometime” and, altough it relies on material considerations, i am unable to tell the reason of “sometime”.

I personnally don’t see anything from my 2 harddisks, one ide and the other sata, without being sure that it is related to the fact that both start with a primary partition.

The issue is not windows dependent, as it only seems to be based on the harddisk configuration, and space taken by the mbr and ebr, and not their content, but maybe could depend upon how that disk has been formatted, partititionned, and maybe upon what software was used to write the mbr.