Determing # of Clusters on Hard Disk

I'm sorry, HDDscan reports sectors, not clusters. How can I determine the # of sectors on my drive?

Cliff Spitser wrote:

I'm sorry, HDDscan reports sectors, not clusters. How can I determine the # of sectors on my drive?

Look under programs>accessories>system tools>system information>system summary>storage>disks

OK, Thanks. Got it.

Cliff

Ayoub,

I just noticed that if I choose "Disks" it just shows my internal boot drive and it shows the # of sectors. If I choose "Drives" it then shows my external drive but does not list the sector size of the # of sectors.

What version of Windows are you using?

In Windows 7, I can see my USB drives under Disks. If you plug the drive in after you started System Information, you will probably need to refresh the display (refreshing Drives may not refresh Disks, etc.).

I have XP pro

Can you get the information from chkdsk? One allocation unit is usually 4K or 8 sectors.

Norton disk doctor says :
"512 bytes in each allocation unit
1,953,504,623 total allocation units on disk"

I guess an allocation unit is a sector, right?

It looks like it for that drive. What formatting is being used? 512B allocation units seems kind of small (NTFS default is 4K), especially for a drive that size. Unless Norton is just looking at the drive as a whole and not a formatted partition.

NTFS
I purchased this drive, Toshiba 1TB 3 1/2 inch external, about a month ago. After using it for a while I noticed that it was a FAT32 file system. I got a lot of advice from this forum that I shouold convert it to NTFS. So, I did that using the windows convert.exe.

Okay. That explains it.

Did I do the right thing?

In this case, it's probably not really right or wrong. When you use convert to change from FAT32 to NTFS, it will use the small allocation unit if the partition is not aligned correctly to use 4K. Personally, I prefer 4KB and I definately wouldn't use 512B on a system drive.

I suppose you could change it, but you would need to use a program capable of changing the cluster size or else copy all the data off and reformat it to NTFS 4KB (you may need to resize or delete and recreate the partition to get the proper alignment).

would acronis disk director do the job without copying all the data out and then copying it back?

Would you be using DD 10 or DD 11 Advanced (DD 11 Home doesn't have that feature)?

As far as I know, it should work okay. There wasn't any problems in a quick test I just ran.

Please note that I always recommend creating an Entire Disk Image backup before making partitioning changes (including formatting changes), just in case something goes wrong.

I don't know which version I would use. I do not own disk director. I just downloaded the home trial versioin today.

I agree with your recommendation to back up the data first. If I do that, then I would think all I need is a disk format utility. Couldn't I just use the Windows format button and choose the 4K allocation unit size? If so, would I choose "quick format"?

Well, I just noticed that my internal boot drive also has a sector size of 512 bytes. Should I reformat that one also.?

A sector size of 512 bytes is normal. It's the cluster size that the formatting uses. A 4K cluster is normal for NTFS. Make sure you're looking at the correct thing. Making changes to the system partition is going to be more difficult using standard Windows procedures.

Yes, you can just reformat with the correct options. Or, if you can't get the cluster size you want, delete the partition and recreate it and then format it. Once finished, copy all the data back. Using the Quick Format option is usually fine. However, since you have bad sectors you it may be best to run chkdsk /r on the partition after formatting and before placing any files one it.

OK. You have been extremely helpful.

I am backing up my data now. Then I will reformat the drive and then copy the data back. Is that right?

I just have a few more questions.

1. Is an allocation unit the same as a sector? or is it a cluster? When formatting, I would choose allocation unit = 4K right

2. When I run hddscan (freeware that a local disk repair shop recommends) it reports 81 bad sectors on my external drive. That is what started me on this long exploration. I later ran norton disk doctor (Just info, not repair) and it reports "0 KB in bad sectors" I am now thinking that I have no bad sectors, and that the disk is fine except for the allocation unit size.

You have the procedure right.

1. An allocation unit is not the same as a sector. Usually, multiple sectors are included in one unit. NTFS default of 4K (1 cluster) = 8 sectors in each allocation unit. 4K clusters should be fine.

2. HDDScan may be reporting bad sectors on the drive that have already been remapped by the drive. Each drive has spare sectors it uses for this. When the spare sectors run out, you start seeing bad sectors show up in chkdsk reports.

In most cases, you will want to monitor the number of bad sectors. If the number of bad sectors continue to increase, consider replacing the drive.

Thanks for explaining the sector/allocation unit relationship. I'm climbing up the learning curve.

I didn't think that a drive could remap sectors all by itself. I thought that to remap a bad sector you would have to run chkdsk sith the /f parameter, or run diskdoctor with the "fix errors" box checked. I have not done either one of these. That is why I was thinking that hddscan is reporting erroneous info.

chkdsk /r is the one that scans for bad sectors.