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ok....i just reformatted my 80gig seagate barracuda through windows (was a slave drive)

after it reformatted, windows only sees it as a 74.6gig HD. Not only that...but after i reformatted it shows as already having 66.8mb used.
I didnt load anything on it yet. Just reformatted


now my question is.......why isnt it showing the full 80gig and why is there 66mb used when there is nothing on it after a reformat?

What Filesystem?

The 66MB is probably the MFT (Master File Table) if you are using NTFS. As for why it's showing 74.6 GB, I've never had a harddrive show the advertised size. Like right now I have 2 80GB drives in a RAID array but my partition sizes according to windows only adds up to 151.67 GB. I'm sure there is an answer somewhere.

Because a megabyte is based on 1,400,000 some odd bytes, not 1,000,000.. eGo

The drive only showing as 74.6 is due to space used for the FAT tables or MFT depending on what file system you used. As for the 66 megs already used you got me.

heh, about the size of the drive. From Seagate's website:

Capacity:
Capacity is the amount of data that the drive can store, after formatting. Most disc drive companies, including Seagate, calculate disc capacity based on the assumption that 1 megabyte = 1000 kilobytes and 1 gigabyte=1000 megabytes

Windows counts 1 gigabyte as 1024 megabytes (Which it really is, but for some reason hdd makers thought it'd be user to use a base 10 system instead of base 2)

81920 MB in a TRUE 80 Gigabyte drive (1024*80)
vs
80000 MB in your Seagate


So take the extra 1920 MB's your supposed to get in a true 80Gb drive and subtract it from Seagate's Base10 drive of 80,000 and you get 78080, or 78.1GB.

That extra 4GB probably got lost because of 2 things. 1. Although Seagate states 1 GB = 1000 MB it's pretty hard to actually accurately get that, so it might be 1GB = 999MB, etc and 2. Your FAT/NTFS cluster size. Fat uses larger cluster sizes, which means more disk space is lost , versus NTFS which uses smaller clusters (3k I think) but has the master file table, the MFT mirror copy, and the MFT log. If your using WinXP with it's underlying stuff in NTFS2 it'll take up a bit more room.

HTH

well it was formatted under win2k, so its NTFS

well that helped a little bit more

thanks for lengthy explination judg3

bugs me.....wish I could use the full 80gigs as advertised

you are.

Greg

exactly as judg3 said. I also believe it has to do witht hte fact a computers number system starts with 0 and not 1. That is the reason for the offset. (1k equaling 1024 bytes as opposed to 1000)