Learn about the technologies behind the Internet with The TCP/IP Guide!
NOTE: Using robot software to mass-download the site degrades the server and is prohibited. See here for more.
Find The PC Guide helpful? Please consider a donation to The PC Guide Tip Jar. Visa/MC/Paypal accepted.
View over 750 of my fine art photos any time for free at DesktopScenes.com!

[ The PC Guide | Systems and Components Reference Guide | Hard Disk Drives | Construction and Operation of the Hard Disk | Hard Disk Packaging and Mounting ]

Form Factor Comparison

For ease of comparison, the summary table below lists all of the standard internal hard disk form factors with their dimensions, typical platter sizes found in hard disks that use the form factor, and common applications:

Form Factor

Profile

Platter Size (in)

Width (in)

Depth (in)

Height (in)

Application

5.25"

Full-Height

5.12

5.75

8.0

3.25

All drives in early 1980s; Large capacity drives with many platters as late as the mid-1990s

Half-Height

5.12

5.75

8.0

1.63

Early 1980s through early 1990s

Low-Profile

5.12

5.75

8.0

1.0

Quantum Bigfoot, mid-to-late 1990s

Ultra-Low-Profile

5.12

5.75

8.0

0.75 - 0.80

Quantum Bigfoot, mid-to-late 1990s

3.5"

Half-Height

2.5, 3.0, 3.74

4.0

5.75

1.63

High-end, high-capacity drives

Low-Profile

2.5, 3.0, 3.74

4.0

5.75

1.0

Industry standard, most common form factor for PC hard disks

2.5"

19 mm Height

2.5

2.75

3.94

0.75

Highest-capacity 2.5" drives, used in full-featured laptop systems

17 mm Height

2.5

2.75

3.94

0.67

Mid-range capacity drives used in some laptop systems

12.5 mm Height

2.5

2.75

3.94

0.49

Low-capacity drives used in small laptops (subnotebooks)

9.5 mm Height

2.5

2.75

3.94

0.37

Lowest-capacity drives used in very small laptops (mini-subnotebooks)

PC Card

Type I

1.8

2.13

3.37

0.13

Not used for  hard disks (yet?)

Type II

1.8

2.13

3.37

0.20

Smaller-capacity expansion hard disks for laptops and consumer electronics

Type III

1.8

2.13

3.37

0.41

Higher-capacity expansion hard disks for laptops

Compact
Flash

Type I

1.0

1.69

1.42

0.13

Smaller-capacity flash cards for digital cameras, hand-held computers and consumer electronics; not used for  hard disks (yet)

Type II

1.0

1.69

1.42

0.20

Larger-capacity flash cards and hard disks for digital cameras, hand-held computers and consumer electronics

Next: External Hard Disks


Home  -  Search  -  Topics  -  Up

The PC Guide (http://www.PCGuide.com)
Site Version: 2.2.0 - Version Date: April 17, 2001
Copyright 1997-2004 Charles M. Kozierok. All Rights Reserved.

Not responsible for any loss resulting from the use of this site.
Please read the Site Guide before using this material.
Custom Search