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Does a standard hard disk format, not the quick format option, in Windows Vista, do a write/read check of all sectors and mark any sector "bad" if they are not OK? Or is that kind of thorough check not done when formatting a hard disk?

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migrated from Jan 13 '11 at 11:38

This question came from our site for system and network administrators.

This is a question for superuser rather than serverfault? – AliGibbs Jan 13 '11 at 10:57

From what I remember it does the check but only for sectors in which it want to place the filesystem structures. At least that was the case in the Windows 9x days. Considering that full format of a 1TB drive doesn't take over 4h that would seem to be the case today too.

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I cannot find any documentation on weather it reads only or writes also.;en-us;302686&Product=winxp

When you choose to run a regular format on a volume, files are removed from the volume that you are formatting and the hard disk is scanned for bad sectors. The scan for bad sectors is responsible for the majority of the time that it takes to format a volume.

I make the assumption the scan is the same surface scan a chkdsk /r performs.

I assume scan means Read also.

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I can't add comments, so I'll write an answer.

I don't know what the Windows tool will really do, but if I were in your shoes, I'd use the hard drive manufacturer tools to accomplish that task.

But if I was faced with a disk with bad sectors, I'd replace it without trying to fix it, since I'm told that broken disk area could expand over time.

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That a sector is readable doesn't assure that it is writable. I'm convinced that neither the CHKDSK nor FORMAT utilities do read-after-write testing.

The S.M.A.R.T. tests (short and long) are a read-only situation.

Spinrite and similar are capable of true read-after-write testing. I suppose that bulk erasure software would also identify sectors that can't be written to.

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