In most cases hard drive model numbers tell you the capacity of the device, the rotational speed of the motor, the interface type and speed and much more. Often the model number is all that is required to understand the type of drive that you have.

Knowing the model number of your particular drive can also prove handy when you have experienced hard drive failure. Each hard drive Vendor have different format to tell the hard drive capacity, speed etc.. information.

Here are some popular disk drives models for your reference.

Note: Conventions used in this post:

 w, x, y, and z are numerical values
a, b, and c are for letters.

Understanding HGST hard drive model number:

HGST ATA drive

HDSwxyabcz0

HDS refers to Hitachi DeskStar
w = the spindle speed of the disk. Only the first two digits (72 for a 7200RPM drive) are given
x = the capacity, in gigabytes, of the largest member of the drive family, divided by 10.
y = the capacity, in gigabytes, of the drive, divided by 10.
a = Generation code, although this value can also be used to identify the maximum number of platters in the drive family
- P = 1
- D = 2
- V = 3
- K = 5
b = L, which stands for a low profile 3.5x1" form factor drive.
c = the drive's interface; AT= PATA, SA=SATA, A3=SATA 3.0 gbps
z = the size of the disks buffer; 2 for 2MB buffer models, 8 for 8MB and 6 for 16MB.
0 = Reserved for future use by Hitachi.

Note on Deskstar Families: You may sometimes have to use the values for 'a' as well as 'x' to determine which family a drive is from. For example, drives from the 7K250 and T7K250 families will have the same value for 'x' (25) but different platter counts 'a.' A T7K250 drive will have a 'D' for its two platters, while a 7K250 drive will have a 'V' for its maximum of 3 platters. On the flip side, a 7K400 and 7K500 drive will have the same value for 'a' (K) but different values for 'x.'

Example: HDS722516VLSA80 is a 7200RPM 160GB SATA drive, from the 7K250 family that has an 8MB buffer.

Hitachi SCSI drives

H F P SP TC MC x Z IF x B x
Hitachi Family Series Prefix RPM Top Capacity Model Code Height Interface Feature Code

F:
D = Deskstar
T = Travelstar
U = Ultrastar

P:
S = Standard (default, if no series name prefix)
C = Compact
A = Auto

SP:
36 = 3600 rpm
42 = 4200 rpm
54 = 5400 rpm
72 = 7200 rpm
10 = 10,000 rpm
15 = 15,000 rpm

TC:
Top capacity available for a particular drive release:
25 = 250GB (first two significant digits)
18 = 180GB

MC:
Unique model code

Z:
z-Height:
L = 1"
7 = 7 mm
9 = 9.5 mm
5 = 5 mm
IF:
16 = Ultra 160, 68 pin
18 = Ultra 160, 80 pin
36 = Ultra 320, 68 pin
38 = Ultra 320, 80 pin
F2 = Fibre channel 2GB
SS = Serial-attached SCSI

B:
Feature Code assigned by business unit (e.g., cache buffer size)

For example:

HTS545050B9A300 = 500GB, SATA 3Gb/s

H = Hitachi
T = Travelstar
S = Standard (vs E for Enhanced availability)
54 = 5400 RPM
50 = Full capacity — 500GB
50 = Capacity this model, 50 = 500GB (40 = 400GB, 32 = 320GB, 25 = 250GB, 16 = 160GB, 12 = 120GB)
B = Generation code 9 = 9.5mm (the height of the hard drive)
A3 = Interface - in this case SATA 3Gb/s
0 = Reserved by the manufacturer
0 = Feature code,
0 = None - in this series a 1 indicates that the drive supports Bulk Disk Encryption, this can have a different meaning for different generations and families of hard disk drive.

Understanding Seagate hard drive model number

ATA hard drive

STxya

ST stands for Seagate Technology
x = 3, which means the drive is a 3.5" wide 1" thick low profile drive (all of Seagate's desktop drives ship in this form factor)
y = the capacity of the drive in megabytes
a = Interface; A = PATA and AS = SATA

Example: ST3160023A is a 3.5x1 inch PATA drive with a capacity of 160023MB, which when divided by 1000 to convert to gigabytes, comes out to a retail capacity of 160GB.

SCSI hard drive

STaxb

ST refers to Seagate Technology
a: Form Factor
- 1 3.5-inch, half-height, 1.6-inch high
- 3 3.5-inch, low-profile (LP), 1-inch high
x: Formatted capacity in Mbytes
b: Interface
- DC Differential, 80-pin Single Connector Attachment (SCA)
- LC Low Voltage Differential, 80-pin SCA
- LCV Same as LC, but with an increased cache size
- LW Low Voltage Differential, 68-pin Wide SCSI Connector
- LWV Same as LW, but with an increased cache size
- N SCSI, 50-pin Narrow SCSI Connector
- ND Differential, 50-pin Narrow SCSI Connector
- W SCSI, 68-pin Wide SCSI Connector
- WC SCSI, 80-pin SCA (Hot Swapable)
- WD Differential, 68-pin Wide SCSI Connector
- FC Fibre Channel, 40-pin SCA
- FCV Same as FC, but with an increased cache size


STaxbc-d
ST: Once again, Seagate Technology

a: Form Factor
- 1 3.5-inch, half-height, 1.6-inch high
- 2 5.25-inch, half-height, 1.6-inch high
- 3 3.5-inch, low-profile (LP), 1-inch high
- 4 5.25-inch, full height
- 5 3.5-inch, 0.75-inch high
- 6 9-inch
- 7 1.8-inch
- 8 8-inch
- 9 2.5-inch, 0.75-inch high
x: Formatted capacity in Mbytes
b: Interface
- DC Differential, 80-pin Single Connector Attachment (SCA)
- E : ESDI Interface
- FC Fibre Channel, 40-pin SCA
- J SMD/SME-E Interface
- K IPI-2 Interface or Part of a Kit
- LC Low Voltage Differential, 80-pin SCA
- LW Low Voltage Differential, 68-pin Wide SCSI Connector
- N SCSI, 50-pin Narrow SCSI Connector
- ND Differential, 50-pin Narrow SCSI Connector
- NM SCSI, 50-pin Narrow SCSI Connector, Macintosh Compatible
- NV SCSI, 50-pin Narrow SCSI Connector, Netware Ready
- P PCMCIA (PC Card) Interface
- R ST412/RLL Interface
- S Synchronized Spindle or Synchronous SCSI
- W SCSI, 68-pin Wide SCSI Connector
- WC SCSI, 80-pin SCA (Hot Swapable)
- WD Differential, 68-pin Wide SCSI Connector
- Unspecified (value not present): ST412/MFM Interface
c: PR Drive shipped with installation software and a Seagate controller or host adapter.
d: Access time; 0=Standard, 1=Faster

For example:

# ST373455SS can provide following information:

  • ST – Brand identity
  • 3 – Form Factor (3 = 3.5″)
  • 73 – Disk size / Capacity in GB i.e. 73GB
  • 4 – Reserved for future use
  • 5 – RPM ( 5 = 15k and 0 = 10K)
  • 5 – Generation
  • SS – Indicates interface i.e Serial Attached SCSI

Understanding Maxtor hard drive model number

ATA Hard drive

xayb0

xa = drive family
- 6Y = DiamondMax(DM) Plus 9
- 6B = DM10
- 6L = DM10 RoHS compliant version
- 6H = DM11
- 7B = MaxLine(ML)III
- 7L = MLIII RoHS compliant
- 7H = ML Pro
- 4R = DM16
- 2F = Fireball 3
- 6E = DM Plus 8
- 5A = ML II
- 7Y = ML Plus II
y = the capacity of the disk, in gigabytes. Drives less than 100GB will have a leading zero (80GB is denoted as 080, etc)
b = buffer size and interface
- J = 2MB PATA with ball-bearing motor
- L = 2MB PATA with fluid dynamic bearing (FDB) motor
- P = 8MB PATA
- R = 16MB PATA
- M = 8MB SATA
- S = 16MB SATA
- F = 16MB SATA 3gbps
All Maxtor SKUs have a zero at the end. It may have a value, but I'm not aware of one.

Example: A Maxtor drive with a model number of 6Y200P0 is a 200GB 7200RPM PATA drive with an 8MB buffer from the DiamondMax Plus 9 family.

SCSI hard Drive

axbc

a: Model
- 8E Atlas 15K II
- 8B Atlas 10K IV
- 8C Atlas 15K
- 8D Atlas 10K V
- AT Atlas I
- EN ProDrive LPS
- EP ProDrive LPS
- GM ProDrive LPS
- HN Atlas II
- KN Atlas IV
- KW Atlas 10K III
- KU Atlas 10K III (U320 Version)
- MU ProDrive
- PI ProDrive ELS
- PX Viking II
- RR LPS (RoadRunner)
- TD Atlas III
- TN Atlas 10K
- TY Atlas 10K II
- VK Viking
- XC Atlas V
x: Capacity in Gb or Mb, depending on the age of the drive.
b: Interface
- D SCSI Wide, 68-pin High Voltage Differential (HVD)
- F Fibre Channel
- J SCSI SCA, 80-pin
- L SCSI Wide, 68-pin Low Voltage Differential (LVD)
- S SCSI, 50-pin Single Ended (SE)
- W SCSI Wide, 68-pin Single Ended
- S Serial Attached SCSI
c: Active recording surfaces, or number of platters x 2. No longer used as of Atlas 10K IV, replaced with a 0 instead


Understanding Samsung Hard Drive(ATA) model number

SPxyza

SP refers to SpinPoint, the brand name of all Samsung HDDs
x = Capacity in GB / 10
y = 0 or 1, Only applies to PATA drives; 0 for 2MB buffer, 1 for 8MB. All Samsung SATA drives have 8MB buffers (some of Samsung's newer SATA SKUs show a zero here despite their 8MB buffer)
z = number of active recording heads; 2, 3, or 4 depending on the geometry of the drive.
a = Interface; N for PATA drives, C for SATA drives.

Example: SP1213C is a 120GB SATA drive, with 8MB buffer, and 3 active recording surfaces (both sides of one platter and one side of a second platter)


Understanding Western Digital SCSI Hard Drive model number

WDx0ab

WD stands for Western Digital
x = the capacity of the drive in GB
WD puts an additional zero after the capacity value
a = buffer size and spindle speed
- B = 2MB 7200RPM
- J = 8MB 7200RPM
- K = 16MB 7200RPM
- G = 8MB 10,000RPM
- S = 8MB 7200RPM RAID Edition
- Y = 16MB 7200RPM RAID Edition 2
b = interface of the drive
- B = PATA
- D = 1.5 gbps SATA
- R = 1.5 gbps SATA w/ NCQ
- S = 3 gbps SATA

For more WD hard drive model number info, see http://www.datarecoverytools.co.uk/drsdownloads/Western%20Digital%20Model%20Numbers.pdf

Or

Western Digital Model Numbers.pdf 

Understanding Fujitsu SCSI Hard Drive model numbers

Mabcxd
M: Fujitsu ID

a: Product Family
- A AL Series
- C CAT series
- D Dynamo
- H HN series
- P PB series
b: Model Series, sequential based on newness/speed. ie U newer than S, newer than M
- G, P, and T: 10,000RPM drives
- M, S, and U: 15,000RPM drives
c: Form Factor
- 2 2.5 inch
- 3 3.5 inch
x: The capacity * 10 measured in GB; 064 = 6.4 GB : 182 = 18.2GB
d: Interface
- FC Fibre Channel
- LC LVDS (SCSI ULTRA-2) SCA connector
- LP LVDS (SCSI ULTRA 2) 68 pin connector
- SC SCSI SCA
- SP SCSI 68 pin
- SS SCSI-2 single ended

Understanding Maxtor/Quantum SCSI Drive model number

axbc

a: Model
- 8E Atlas 15K II
- 8B Atlas 10K IV
- 8C Atlas 15K
- 8D Atlas 10K V
- AT Atlas I
- EN ProDrive LPS
- EP ProDrive LPS
- GM ProDrive LPS
- HN Atlas II
- KN Atlas IV
- KW Atlas 10K III
- KU Atlas 10K III (U320 Version)
- MU ProDrive
- PI ProDrive ELS
- PX Viking II
- RR LPS (RoadRunner)
- TD Atlas III
- TN Atlas 10K
- TY Atlas 10K II
- VK Viking
- XC Atlas V
x: Capacity in Gb or Mb, depending on the age of the drive.
b: Interface
- D SCSI Wide, 68-pin High Voltage Differential (HVD)
- F Fibre Channel
- J SCSI SCA, 80-pin
- L SCSI Wide, 68-pin Low Voltage Differential (LVD)
- S SCSI, 50-pin Single Ended (SE)
- W SCSI Wide, 68-pin Single Ended
- S Serial Attached SCSI
c: Active recording surfaces, or number of platters x 2. No longer used as of Atlas 10K IV, replaced with a 0 instead

Understanding IBM SCSI drives model numbers

IC FF H xxx IF xx SP
Internal Code Form Factor Height Unique code Interface Unique code RPMs

FF:
35 = 88.9 mm (3.5 inch)
25 = 63.5 mm (2.5 inch)

H:
L = 25.4 mm (1 inch)
T = 12.5 mm (0.49 inch)
N = 9.5 mm (0.37 inch)

IF:
UW = Ultra SCSI 68-pin Wide
UC = Ultra SCSI 80-pin SCA
F2 = FC-AL-2 (2 Gbit)

SP:
04 = 4200
05 = 5400
07 = 7200
10 = 10,000
15 = 15,000