In my latest WD Install guide, it says (on p7) that
if the drive is the only device on the cable the setting
is to jumper 4&6.  This is the "jumper parking" position
and keeps it from getting lost (for possible use later).
This is from the 44 page booklet in the section called
Standard Jumper Settings for 10-pin WD hard drives.
(I am aware that the sticker on the face of the drive
indicates NO jumper is "also" for a single stand-alone drive.)

Note that lots of drives have a "sometimes poorly documented"
parking position for the jumper(s), so this is not something
limited to just WD drives.

                        Rick Glazier

From: "Demetri Kolokotronis" <[log in to unmask]>
> No jumper is single or master.
> This is default.
>
> 9 7 5 3 1
> o o o o o        PWR
> o o o o o       o o o o
> 108 6 4 2
>
> 5&6 is master with slave.
> 3&4 is slave.

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