13W3 Stecker.jpg
Male 13W3 plug.
Type Computer video connector
Superseded by VGA connector / DVI
Hot pluggable yes
External yes
Video signal Analogue RGB or monochrome
DB13W3 Pinout.svg
Pin Sun SGI / DCC
Pin 1 Ground / DDC-SCL Monitor ID bit 3 /
Data clock (SCL)
Pin 2 Vertical sync / NC Monitor ID bit 0 /
Bi-directional data (SDA)
Pin 3 Sense #2 / NC Composite sync /
Composite sync
Pin 4 Sense ground / DDC ground Horizontal drive /
Horizontal sync
Pin 5 Composite sync Vertical drive /
Vertical sync
Pin 6 Horizontal sync / DDC-SDA Monitor ID bit 1 /
DDC (+5V input)
Pin 7 Ground / VSYNC Monitor ID bit 2 /
DDC ground
Pin 8 Sense #1 / NC Digital ground /
Pin 9 Sense #0 /NC Digital ground /
Pin 10 Composite ground Sync ground /
A1 Red Red
A2 Green
(Gray for monochrome)
(Gray for monochrome)
A3 Blue Blue

DB13W3 (also known simply as 13W3) is a particular style of D-subminiature connector commonly used as an analog video interface connector that was used primarily on Sun Microsystems, Silicon Graphics and IBM RISC workstations, as well as some displays from Apple Computer, NeXT Computer and Intergraph Corporation . The 13W3 connector is no longer used with modern displays, which have generally moved on to VGA or DVI connectors. The DB13W3 (but with high current pins instead of high frequency ones used for video applications) connector is also used by some 3Com SuperStack Ethernet switches to carry DC power.

The connector contains 10 standard signal pins and 3 larger positions that can be fitted with either special pins with two concentric contacts for coaxial cable or with special high current pins. When used for video signals on the computer side, the pins are female but the coaxial connectors in the large positions are male. The coaxial connectors carry the video signal split into red, green/gray, and blue; the standard signal pins carry four grounds, three "sense" pins used to communicate with the monitor, vertical sync, horizontal sync, and a composite sync signal.

The 13W3 connector can be converted into a standard VGA connector using cables and adapters that are commonly available. This allows modern multisync monitors, which are common on today's computers, to be used with these workstations as long as they are sync-on-green compatible. Likewise, as many newer Sun monitors support multisync, similar cables can be used to connect them to modern computers.

Even though 13W3 is a standard connector the sync signals are maintained on different pins based on the display and system. Sun Microsystems, Intergraph, IBM RISC and SGI have a different set of pins used for the monitor sense IDs and the sync signals. Sun even has two different pinnings: the "classic" one, and one with DDC that was used at least on the UPA graphics adapters (Creator 3D, Expert 3D) and for the corresponding monitors (GD5410, GD5510). This can make matching the correct cable to the monitor virtually impossible. Many monitors with 13W3 connectors do not support separate sync as supplied on most PC systems. Other converters exist to allow connecting newer monitors with VGA connectors to the older systems and workstations. The most popular of these is a cable that allows you to set the sync signals with a series of DIP switches built into the cables.

See also

  • List of display interfaces

External links