• We’re currently investigating an issue related to the forum theme and styling that is impacting page layout and visual formatting. The problem has been identified, and we are actively working on a resolution. There is no impact to user data or functionality, this is strictly a front-end display issue. We’ll post an update once the fix has been deployed. Thanks for your patience while we get this sorted.

Exact drive size for 1TB m550 and Samsung EVO's?

N

nehalemi7

Junior Member
I'm looking to replace some 1 TB disks with 1 TB SSDs. The disks in question are going to go in RAID1's, so they need to be the same size or bigger than the hard drives I'm currently using. (I'd like to remove one side of the RAID, rebuild to a SSD, and repeat for the other drive) I can't find the exact sizes in bytes of either of these drives.

I used msinfo32, components > storage > disks to find the size of the 1 TB drives we have now. They're Western Digital RE3 1 TB's, so 1,000,202,273,280 bytes. If you have one of these drives, can you please run msinfo32 or similar to verify the exact size in bytes of the drives?
 
My 1 TB Samsung 840 EVO size is 931.39

After Over Provisioning by 10% which Samsung recommends, it is 838 GB

AS SSD Benchmark with IRST 12.8.0.1016 in RAID 0 (W8.1)

2qa8m7s.jpg
 
I wouldn't mess with all that - if you have the SATA ports to pull it off, just install the two new SSDs as a RAID1, so you have both RAIDs online and healthy at the same time, and then migrate your data over that way. It'll take like half the time.
 
dave_the_nerd said:
http://www.anandtech.com/show/7173/...w-120gb-250gb-500gb-750gb-1tb-models-tested/2

and

http://www.anandtech.com/show/7864/crucial-m550-review-128gb-256gb-512gb-and-1tb-models-tested

Indicate there is default overprovisioning (aka spare area) on both the 840 EVO and the M550.
Click to expand...

please explain where is this OP??? My 1 TB drive is 931 GB formatted which makes sense due to the diff. calculation methods used by SSD Manufacturers and Windows

Now when I run Magician for the first time, it shows the drive has a 931 GB capacity as well and recommends a 10% OP

I have OPed by 1st drive (C: where the OS is installed) by 30% giving me a space of 651 GB and 591 GB is free after installing all my apps/games

My D: Drive is only OPed by 10% since I need it to be large enough to hold any videos I put on it so it's 838 GB

Also, people on NBR forums told me the drive does not have a manufacturer OP. Can you point to where exactly you read that in the above links?
 
JohnnyLucky said:
Although the capacity is advertised as 256GB, the actual capacity is 238GB due to overprovisioning.
Click to expand...
Actually that difference between 256GB and 238GB has nothing to do with overprovisioning, it is due to the way drive makers advertise size and how Windows reports size.

To a drive maker, 1GB = 1,000,000,000 (1,000^3)

To Windows 1GiB= 1,073,741,824 (1,024^3)

You can use a ratio of 93% to convert: 93% of 256GB = 238GiB

So, if Windows is reporting "238GB" (technically 238GiB), then you have no overprovisioning.
Click to expand...

ARGH: This was NOT due to overprovisioning!!!

The difference between what the manufacturer reported, in your case 256GB and what the OS reports 238GB is ONLY due to the difference between how a manufacturer reports the size using 10^9 as a GB versus how the OS reports a GB using binary 2^30.

SO the manufacturer states 256GB which is 256 * 10^9 or 256 * 1,000,000,000 = 256,000,000,000 Bytes
Since the OS is using 2^30 or 1,073,741,824 the size the OS reports will be 256,000,000,000 / 1,073,741,824 = 238.42GB

This will be the same on ANY hard drive SSD or not and will be the same ratio on ACT hard drive regardless of size.
This has been true since hard-drives have been put in to computers!!!

If the SSD magician HAD created space on the drive you would have less than the 238GB as reported by the OS and you would see it as unallocated space in the Windows Disk Management Window.
Click to expand...

http://www.tomshardware.com/forum/278446-32-samsung-magician-provisioning
 
Last edited:
hmm, seems you are right there is a 7% OP that is hidden from the user:

I apologize for the delay in responding. I got side tracked quite a bit. Had to do a lot of research too and get confirmation for the following information.

I have confirmed that Samsung does in fact ship their ssd's with 7% capacity reserved for overprovisioning which is hidden from view, even in the Samsung SSD Magician.

When the Samsung SSD Magician shows 0% provisioning that actually means the standard factory 7% overprovisioning has not been expanded or contracted by the user. It is simply in the 7% default mode.

At the same time we also have a fairly new concept called 0% provisioning which first appeared in published articles about this time last year. Like the Samsung Magician 0% overprovisioning, the new concept should not be taken literally or at face value. These are situations where 0 does not mean 0.

The concept of 0% provisioning turned out to be very confusing for a lot of individuals. If I understood the information correctly the SSD manufacturers are using the standard unformatted to formatted ratio from hard disk drives to come up with a difference of 7.37%. That 7.37% is used for overprovisioning and a few other ssd features. As near as I can tell this is what Samsung, Intel, OCZ and other ssd companies are probably doing with their newest ssd's.
Click to expand...
 
dave_the_nerd said:
I wouldn't mess with all that - if you have the SATA ports to pull it off, just install the two new SSDs as a RAID1, so you have both RAIDs online and healthy at the same time, and then migrate your data over that way. It'll take like half the time.
Click to expand...

I don't have spare SATA ports on the server I have in mind. The OS is on the thing I want to migrate as well. :/
 
nehalemi7 said:
I don't have spare SATA ports on the server I have in mind. The OS is on the thing I want to migrate as well. :/
Click to expand...

Oh.

Well, if the SSDs are ever-so-slightly-smaller than the 1TB HDDs you have, then shrink your partition by a few GB to give yourself breathing room, do the 1-at-a-time swap like you were going to, and then expand it to fill the SSDs.

You do have some free space on these drives, right?
 
dave_the_nerd said:
Oh.

Well, if the SSDs are ever-so-slightly-smaller than the 1TB HDDs you have, then shrink your partition by a few GB to give yourself breathing room, do the 1-at-a-time swap like you were going to, and then expand it to fill the SSDs.

You do have some free space on these drives, right?
Click to expand...

There's tons of free space on the drives (>50% free), but I'm not aware of a non-trivial way to shrink a RAID.
 
nehalemi7 said:
There's tons of free space on the drives (>50% free), but I'm not aware of a non-trivial way to shrink a RAID.
Click to expand...

You're just shrinking the partition. You can do it in Windows Disk Management. (Right click - Shrink Volume)

Unless your particular RAID software/controller won't like it. But you can try.
 
dave_the_nerd said:
You're just shrinking the partition. You can do it in Windows Disk Management. (Right click - Shrink Volume)

Unless your particular RAID software/controller won't like it. But you can try.
Click to expand...

You're right, that does shrink the partition, but that does not shrink the actual RAID.
 
What RAID controller are you using? Software? Windows RAID? Motherboard RAID?

Fiddling around with a VM, I was able to more or less do it in Windows. (Break mirror, shrink partition to be smaller than new drive, mirror to new drive, break mirror, expand partition to fill new drive, mirror new drive A to new drive B.)

Of course, this assumes that the 932GB disk you have and the 931.39GB SSD aren't the same thing with a rounding error.
 
dave_the_nerd said:
What RAID controller are you using? Software? Windows RAID? Motherboard RAID?

Fiddling around with a VM, I was able to more or less do it in Windows. (Break mirror, shrink partition to be smaller than new drive, mirror to new drive, break mirror, expand partition to fill new drive, mirror new drive A to new drive B.)

Of course, this assumes that the 932GB disk you have and the 931.39GB SSD aren't the same thing with a rounding error.
Click to expand...

I'm using the Intel motherboard RAID (Rapid Storage Technology). What kind of RAID was the VM using?
 
You must log in or register to reply here.

TRENDING THREADS

Back
Top