How to check for 512 or 4096 sector? WD20EARS

WD Internal Drives Desktop & Mobile Drives
1

Got a 2 month old WD20ears HDD which has former been used in a NAS that formatted the drive in some sort of Linux.

Installed in Win 7 x64, made a primary partition and formatted it. Sisoft Sandra then says it runs with 512bytes sectors. 

How do I check if the hard drive is actually lowlevel formatted to 512byte sectors?

If so, how do I lowlevel format back to 4096byte sectors? 

As read here,  http://http://www.storagereview.com/western_digital_caviar_green_2tb_review_wd20ears this hard drive can be formatted in both ways. But how??

I have tried WD’s DLGDIAG for windows, but can’t see anything related to this.

2

The 4096-byte physical sector structure is prerecorded at the factory. There is nothing that any software, including Linux, can do to change that. Some versions of WD20EARS firmware report the physical sector size while other versions do not. Yours appears to be one that doesn’t.

Windows 7 automatically creates aligned partitions, so you will never see any performance difference. However, you could create a misaligned MBR partition using Windows XP and then run a write benchmark against the drive. Compare this against the read benchmark. If there is a significant difference, this will confirm that the drive has 4KB physical sectors. If your drive has an alignment jumper (pins 7 & 8), then you could install this jumper and use Win 7 to partition the drive. The jumper adds a +1 sector offset to each LBA, which means that Win 7 will create a misaligned partition which you could then subject to a write benchmark.

3

OK. Thank you for info. I’m on Win7, so I assume I have no problem at all with this :smiley:

4

If you partitioned and installed Windows 7 on your WD20EARS it will be correctly configured for the 4K alignment.

By default Windows 7 partitions disks for 4K as this type of disk has been available since 09.

No need for alignment software. Which is needed for XP which is not 4K aware.