Best sector offset for 2TB Advanced Format drives?

[Carson Dyle]

Right now I have just two computers in my home, one running WinXP and one Win2k3 Server. I'm installing a couple of new 2TB drives in the Win2k3 server, which isn't capable of correctly aligning the drives. XP is the same.

Both disks will be used only for data, so will have just one large partition each. Right now I'm using diskpar.exe on the XP computer to create the aligned partitions, but one question that I can't find a good answer to is the ideal offset to use on these drives.

The two drives are:

Samsung (Seagate) HD204UI
Western Digital WD20EARS

They appear to have exactly the same drive geometry (according to diskpar):

Cylinders = 243201
TracksPerCylinder = 255
SectorsPerTrack = 63
BytesPerSector = 512
DiskSize = 2000396321280 (Bytes) = 1907726 (MB)

WinXP and W2k3 both align the first sector at an offset of 63 sectors (as they do for all drives), which is unaligned. Googling, I've read suggestions of using 64, 1024, 2048, 4096 sectors. I've also found quite a few guides to aligning partitions on SSDs, but don't know how much of it is applicable to AF drives.

What is the optimal setting?

What does Windows 7 set as the standard offset when partitioning 2TB drives?

 

[mv2devnull]

What does Windows 7 set as the standard offset when partitioning 2TB drives?

2048 sectors, i.e. 1024 KiB.
http://msdn.microsoft.com/en-us/library/windows/desktop/hh182553(v=vs.85).aspx

"Advanced Format" means 4 KiB, i.e. 8 "sectors". Therefore, the partition start just has to be a multiple of 8. (Obviously it cannot be 0, for the partition table uses a bit of space too.)


Ignore the Cylinders, Tracks, etc.

 

[Carson Dyle]

Fantastic. I also just found a little wiki article that claims the same thing - Vista and Win7 both align to sector 2048 by default.

http://www.forensicswiki.org/wiki/Advanced_Format

I'm going with that. Thanks!

 

[tweakboy]

What about me! ,, Does it matter in SSD performance if its 512k vs 4096kb

Im on 512k ,,,,, Connected to SATA 2.0 .. gives 260mbps read dl and 244mbps write

and I get a 7.3 in WEI7 , if I connect it to 3.0 would that get me to 500mbps or so...

 

[mv2devnull]

What about me!

Your issue is not relevant nor directly related to this thread. You already have your own thread.

 

[dac7nco]

Welcome to the forums, Walter Matthau (Carson Dyle)!

Daimon

 

[Carson Dyle]

Welcome to the forums, Walter Matthau (Carson Dyle)!

Thanks!

 

[Coup27]

Your issue is not relevant nor directly related to this thread. You already have your own thread.

Doesn't stop him asking this question in every other thread. I even gave him a personalised test to do to find out which he's clearly not bothered to do.

 

[rseiler]

Carson, I'm in the same situation as you, needing to install a 2TB AF drive (WD20EFRX) in Win2k3--just a secondary drive--and correct me if I'm wrong, but from what I've been able to find, diskparT would actually work:

create partition primary align=

Where there's some number at the end that I'm not sure of yet. I do know that "diskpar creates a partition in sectors (512byte), and diskparT uses kilobytes," so maybe 1024 to conform to what mv2devnull said?

Failing that, what command did you use for diskpar? I see the usage is:
diskpar -s 2

Where 2 (or whatever) would be the drive's number, but beyond that I don't see where you'd specify the offset.

I guess the other option is to at least partition it, and maybe even format it, in Win7, but I'd like to avoid mixing OS's.

 

[Carson Dyle]

It's been a while. Diskpar.exe is very simple, but it's interactive. First, I believe it asks for the partition size (I enter whatever number it says is available), then it asks for an offset and I (IIRC) enter 2048.

But I now have a Windows 7 desktop and I would just partition and format the drive using Windows 7 instead of bothering with any utilities. Don't worry about 'mixing' OSs - you're not - you're just formatting a hard drive.

 

[rseiler]

OK, sounds like I have lots of ways to go then.

Just doing it in Win7 is a popular answer, so I must be wrong about this, but I could have sworn something changed as of Vista that very much tied to partitioning, so I'm a little surprised that they're backwardly compatible.