[SOLVED] Disk somehow smaller than identical drives?

Flodos

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So following up from this thread: https://forums.tomshardware.com/threads/is-it-possible-to-preserve-my-raid-5-array.3565667 (thank you everyone for the quick replies, by the way) I gave up on recovering my data and tried to just format the drives and use windows 10's Storage Spaces to create a new striped array. This ran into issues quickly, as it would only be able to use one out of 3 disks. Checking Disk Manager, which I used for the (non-quick) format in the first place, showed that the drives Storage Spaces could not use were somehow about 120MB smaller than the other one. The drives are identical!

Runing CHKDSK /b after formatting a simple volume on the entire drive brought one of the 'smaller' drives back to the capacity of the other one, and Storage Spaces is able to use it now, but the other one remains smaller than its peers. I have no idea why those mb's are inaccessible, or what to do about it. View: https://imgur.com/a/KW46UJ0
here is a screenshot of Disk Manager showing the smaller drive. Any help is once again humbly appreciated!
 
Solution
All three drives are seen by DMDE as having a sector range of 0 - 5860533167. The difference is that two of them have a 16.8MB whereas the other has a 134MB unknown GUID partition. The difference is 117 MB.

ISTM that you need to r-click each of the GUID partitions and select "Remove the Partition".

Then r-click the top line and select "Reset GPT+MBR Signatures (GPT Off)".

This should clean all the partition information. Now "Apply changes" and reboot. Then set up Storage Spaces.

BTW, you might like to double-click each of the 3TB "New Volume" NTFS volumes and expand the Root. You will then be able to see your old file/folder structure. It's not what I expected to find, based on the information in your other thread.

Flodos

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Skip storage spaces.
You can create striped array in Disk Management.
I'm sorry if I wasn't specific enough, but I'm trying to (re)create a RAID5 array. The option is greyed out in Disk Management (presumably because the motherboard doesn't support it), hence why I am trying to rely on Storage Spaces' Parity option. However, since it is unable to access the 'smaller' drive (see this screenshot View: https://imgur.com/a/qzRrsro
for the error) I don't have the required 3 drives.

While I recognize that this setup won't protect me from many issues past a drive failure, I still want to attempt it if at all possible. And a drive being smaller for no discernible reason vexes me to no end!
 
What does CrystalDiskInfo report for the total number of sectors for each drive?

Sometimes a drive's capacity can be truncated with a HPA (Host Protected Area), in which case a tool such as the HDD Capacity Restore Tool can restore a drive's full native capacity.

Another possibility is that one or more drives may have been shucked from an external enclosure. Did you do this?

Still another possibility is that some BIOS-es (eg Gigabyte Express Recovery BIOS) steal ~2000 sectors to store a backup of the BIOS. However, this wouldn't account for the missing 120MB.

Edit:

Is it possible that Intel's RAID manager has reserved this area for RAID metadata?
 
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Flodos

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Flodos

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What does CrystalDiskInfo report for the total number of sectors for each drive?

Sometimes a drive's capacity can be truncated with a HPA (Host Protected Area), in which case a tool such as the HDD Capacity Restore Tool can restore a drive's full native capacity.

Another possibility is that one or more drives may have been shucked from an external enclosure. Did you do this?

Still another possibility is that some BIOS-es (eg Gigabyte Express Recovery BIOS) steal ~2000 sectors to store a backup of the BIOS. However, this wouldn't account for the missing 120MB.

Edit:

Is it possible that Intel's RAID manager has reserved this area for RAID metadata?
I wasn't able to easily figure out CrystalDiskInfo, and HDD Capacity Restore did not function, giving me the following error: 'error opening driver', my apologies. In my other reply you will find DMDE's info though!

To answer your questions: all 3 drives were new, bought specifically for this array. It could be that Intel's software did as such, but that was before a complete reinstall and multiple formats of the drive, quick and standard. That should wipe anything the previously used software did to the drive, right..?
 
I'm sorry if I wasn't specific enough, but I'm trying to (re)create a RAID5 array. The option is greyed out in Disk Management (presumably because the motherboard doesn't support it),
RAID 5 support in Windows is only available on the Pro version (Pro/Ultimate for Win 7). Windows Home only supports RAID 0/1. It will tempt you with the RAID 5 option, but as you're seeing, it'll be greyed out.

The way RAID 5 on the motherboard usually works is that you go into a BIOS option at boot-up to configure the RAID 5 array. From that point on, Windows sees one virtual drive (the RAID 5 array) instead of the individual drives which make up the array.

And I was gonna reply to your other thread when I saw it, but thought the others sort of covered it well enough. RAID IS NOT A BACKUP. The reason is that if you accidentally delete or overwrite a file from a RAID array, any redundant copies or parity data is immediately deleted or overwritten as well. RAID is for redundancy - to reduce downtime. If your company will hemorrhage a thousand dollars an hour if the shared file server goes down, then you want it to be on RAID. That way a single drive failure does not take your file server down. It still keeps chugging along while you go find a new drive to replace the failed one.

So even if you store your data on RAID, you still need to be making backups. You should never be in a situation where you don't have enough disk space to copy the contents of a RAID array onto another drive. So put your RAID 5 drives back in your old computer, go buy an external hard drive with enough capacity to back it up, back up your RAID data onto the external drive, then move the RAID drives to your new computer and use them without RAID. (Or RAID 1 them if you need redundancy. Or upgrade to Windows 10 Pro if you absolutely need RAID 5.)
 
All three drives are seen by DMDE as having a sector range of 0 - 5860533167. The difference is that two of them have a 16.8MB whereas the other has a 134MB unknown GUID partition. The difference is 117 MB.

ISTM that you need to r-click each of the GUID partitions and select "Remove the Partition".

Then r-click the top line and select "Reset GPT+MBR Signatures (GPT Off)".

This should clean all the partition information. Now "Apply changes" and reboot. Then set up Storage Spaces.

BTW, you might like to double-click each of the 3TB "New Volume" NTFS volumes and expand the Root. You will then be able to see your old file/folder structure. It's not what I expected to find, based on the information in your other thread.
 
Solution

Flodos

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All three drives are seen by DMDE as having a sector range of 0 - 5860533167. The difference is that two of them have a 16.8MB whereas the other has a 134MB unknown GUID partition. The difference is 117 MB.

ISTM that you need to r-click each of the GUID partitions and select "Remove the Partition".

Then r-click the top line and select "Reset GPT+MBR Signatures (GPT Off)".

This should clean all the partition information. Now "Apply changes" and reboot. Then set up Storage Spaces.

BTW, you might like to double-click each of the 3TB "New Volume" NTFS volumes and expand the Root. You will then be able to see your old file/folder structure. It's not what I expected to find, based on the information in your other thread.
YOU FIXED IT! Thank you so very much, removing that partition and resetting those signatures fixed the issue! I'm overjoyed!