Support for WD Advanced Format disks

Bakul Shah bakul at
Tue Aug 10 19:05:39 UTC 2010

On Tue, 10 Aug 2010 19:44:48 +0200 =?utf-8?Q?Dag-Erling_Sm=C3=B8rgrav?= <des at>  wrote:
> I'm looking into a clean, permanent solution for WD Green drives that
> use 4096-byte physical sectors.  To summarize the information I've
> collected so far:
>  - There are several types of WD Green disks.  I am primarily interested
>    in the 1+ TB models: EARS and EADS.
>  - According to WD's own documentation, EARS disks are Advanced Format
>    while EADS disks are not; furthermore, EARS disks have 64 MB cache
>    while EADS disks have only 32 MB. gives an
explanation of what the drive letters mean but they don't
talk about 4k sector size.
>  - There is at least one source that provides model and serial numbers
>    for two EADS disks that seem have the performance characteristics of
>    an Advanced Format disk.  One of them actually reports 4096-byte
>    sectors, the other does not.  I am not entirely certain that source
>    is reliable.

See below.

>  - Advanced Format disks should have a label that clearly describes them
>    as such:


    What models utilize Advanced Format technology?

    Some models of the WD Caviar Green and WD Scorpio Blue
    product families are built using Advanced Format technology.
    Over time more models and capacities will be added. WD drives
    with Advanced Format technology include special installation
    information on the drive label so be sure to read the label
    on your drive before installing it.          ^^^^^^^^^^^^^^

So it seems that only the label distinguishes 4k sector drives.

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