ETX, standing for Embedded Technology eXtended, was first developed by Kontron (formerly *JUMPtec) in the early 2000. It was defined legacy ISA and PCI buses I/O focus, and it is a highly integrated and compact (3.7 × 4.9 inches) (95 × 125 mm) computer-on-module (COM) form factor that can be used in a design application much like an integrated circuit component. Each ETX COM integrates core CPU and memory functionality, the common I/O of a PC/AT (serial, parallel, etc.), USB, audio, graphics, and Ethernet. All I/O signals are full implementation of ISA and PCI buses are mapped to four (X1-X2-X3-X4) high-density, low-profile connectors on the solder side of the module.


Details of ETX in their website and key comparison with XTX and COM Express form-factor


  ETX XTX COM Express
Dimensions 95 × 114 mm 95 × 114 mm
(ETX footprint)
110 ×155 (extended)
95 × 125 mm (basic)
95 x 95 (compact)
Legacy1 support Full legacy Legacy except ISA Legacy except ISA
PCI Express support - 4 Lanes up to 6 Lanes (basic)
PCI Express
Graphic support
- - up to 16 Lanes
Ethernet support 10/100 10/100 10/100/1000
IDE support 2 IDE, 2 SATA2 2 IDE, 4 SATA IDE, 4 SATA
LPC support - Yes Yes
USB support 4 USB 6 USB 8 USB
Audio support Line In/Out, Mic AC'97, Line In/Out, Mic AC'97, Line In/Out,
Mic, AC'97 digital, HDA
Power 5V, 5VSB 5V, 5VSB 12V, 5VSB


1. "Legacy" is defined as the older PC peripherals and bus, such as ISA bus, RS-232 serial, IEEE 1284 parallel, floppy, and PS/2 keyboard & mouse.
2. ETX 3.0 adds SATA via a topside connector on the board.


Mandatory features:

  • Connector X1: PCI bus, USB Audio
  • Connector X2: ISA BUS
  • Connector X3: VGA, LCD, Video, COM 1, COM2, LPT/Floppy, IrDA, Mouse, Keyboard
  • Connector X4: IDE 1, IDE 2, Ethernet, miscellaneous
  • SATA: Two ports via connector on the top side (as of version 3.0)


NEXCOM developed a dedicate carrier board for our ETX module, which will be beneficial to our design partner (or developer) as Customer Reference Board (or CRB), we will provide all documentation as the standard interfaces, pin-defined for our COM developer could very quickly re-make I/O carrier board for their owned IP chassis with own-defined connector of their semi-/ full- customization system.

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