WD decoding the drive numbers

the difference between the WD30EURS and the WD30EURX is the Interface/Connector

WD Western Digital
30 3.0
E TB/3.5 Inch drive,
U Audio/Video Advanced Format - WD A,
R 5400 RPM with 64 MB cache,

Interface/Connector
S SATA 3 Gb/s with 22-pin SATA connector
__SATA 1.5 Gb/s with 22-pin SATA connector (Mobile)

X SATA 3 Gb/s, 6 Gb/s capable with 22-pin SATA connector

the X is capable of twice the speed of the S, but is still rated at 3 Gb/s of the S.

Model Numbers - WD Internal Drives
Model Number Format for OEM and Distribution Channels

Information Sheet
WD’s model number format simplifies inventory management
for distributors and system manufacturers. Capacity points
are key to this format.
Base Model Number
The base model number is composed of six codes:
1. Company initials (WD)
2. Capacity (GB/TB)
3. Capacity unit/form factor
4. Business unit/brand
5. RPM/buffer size or attribute
6. Interface/connector

WD 0000 ABCD
_1____2 3456

Model Number Codes
1 Company Initials
WD
2 Capacity
Two, three, or four digits, supports up to 999.9.
For 1 TB and larger WD Black™ and enterprise drives, the decimal
follows the first digit (e.g., WD1000FYPS is a 1 TB capacity drive).
These drives also use the last digit of the capacity number as a
product code (e.g., WD2003FYYS). This digit does
not
translate to
additional capacity/LBAs.
3 Capacity Unit/Form Factor
AGB/3.5-inch
BGB/2.5-inch
C TB/2.5-inch
D TB/2.5- to 3.5-inch backplane adapter
E TB/3.5-inch
F TB/3.5-inch (new format)
G GB/2.5- to 3.5-inch adapter
H GB/2.5- to 3.5-inch backplane adapter
J TB/2.5-inch
K GB/2.5-inch (12.5 mm z-height)
L GB/2.5-inch (7 mm z-height)
N TB/2.5-inch (15.0 mm z-height)
S TB/2.5-inch (7 mm z-height)
T TB/2.5-inch (12.5 mm z-height)
4 Business Unit/Brand
A Desktop/WD Blue™; WD Green™; WD Black; WD Caviar
®
B Enterprise/WD RE driv
e families (3-platter)
D Enterprise/WD Raptor
®
E Mobile/WD Blue; WD Green;
WD Black; WD Scorpio
®
FDesktop NAS/WD Red™
H Enthusiast/WD VelociRaptor
®
K Enterprise/WD XE; WD S25
L Enterprise/WD VelociRaptor
M Branded/WD Branded
N Branded Advanced Format/WD Branded
P Mobile Advanced Format/WD Bl
ue; WD Green; WD Black;
WD Scorpi

4 Business Unit/Brand (continued)
R Enterprise Advanced Format/WD RE drive families
U Audio/Video Advanced Format - WD AV
V Audio/Video - WD AV
W Enterprise Advanced Format/WD VelociRaptor
Y Enterprise/WD RE drive families (4-platter)
Z Desktop Advanced Format/WD Blue; WD Black; WD Green;
WD Caviar
5 RPM/Buffer Size or Attribute
A 5400 RPM with 2 MB cache
B 7200 RPM with 2 MB cache
C 5400 RPM with 16 MB cache
D 5400 RPM with 32 MB cache
E 7200 RPM with 64 MB cache (<2 TB)
F 10,000 RPM with 16 MB cache
G 10,000 RPM with 8 MB cache
H 10,000 RPM with 32 MB cache
J 7200 RPM with 8 MB cache
K 7200 RPM with 16 MB cache
L 7200 RPM with 32 MB cache
P IntelliPower™/EM (maximum buffer size offered by product)
R 5400 RPM with 64 MB cache
S 7200 RPM with 64 MB cache (2 TB)
T 10,000 RPM/EM (maximum buffer size offered by product)
V 5400 RPM with 8 MB cache (Mobile)
Y 7200 RPM/EM (maximum buffer size offered by product)
6 Interface/Connector
A ATA/66 with 40-pin IDE connector
B ATA/100 with 40-pin IDE connector
C ATA with 33-pin connector
(zero insertion force—ZIF)
D SATA 1.5 Gb/s with 22-pin SATA connector
E ATA/133 with 40-pin IDE connector
F SAS-3 with 29-pin connector
G SAS-6 with 29-pin connector
S SATA 3 Gb/s with 22-pin SATA connector
SATA 1.5 Gb/s with 22-pin SATA connector (Mobile)
T SATA 3 Gb/s with 22-pin SATA connector (Mobile)
X SATA 3 Gb/s, 6 Gb/s capable with 22-pin SATA connector
Z SATA 6 Gb/s with 22-pin SATA connector
Subsequent updates to these definitions will be available in
Change Administration’s
Model Specification
(document number
2096-000101). WD intranet access is required to view or
download the document. To access the document, go to:
http://ift.tt/1IpoN7r
latestspec.aspx?specId=0
(DNA login required).
Model Number Suffix
The model number suffix (characters to the right of the dash
following the model number) is only for in-house use.
Legacy Model Numbers
For instructions on how to decipher WD internal drive model
numbers issued prior to December 2005, refer to the
Legacy
Model and Order Numbers
information sheet (2579-701261).
A copy is available from your
WD representative if required.