Desktop Board Features 
17 
LAN Subsystem 
The LAN subsystem includes: 
•  Intel
®
 ICH9DH  
•  Intel 82566DC Gigabit (10/100/1000 Mb/s) Ethernet LAN controller 
•  RJ-45 LAN connector with integrated status LEDs 
The subsystem features: 
•  CSMA/CD protocol engine 
•  LAN connect interface between ICH9DH and the LAN controller 
•  PCI bus power management 
Related Links: 
Go to the following link for information about LAN software and drivers:  
http://support.intel.com/support/motherboards/desktop 
RJ-45 LAN Connector LEDs 
Two LEDs are built into the RJ-45 LAN connector located on the back panel (see 
Figure 2).  These LEDs indicate the status of the LAN.   
 
Figure 2.  LAN Connector LEDs  
Table 3 describes the LED states when the board is powered up and the LAN 
subsystem is operating. 
Table 3.  LAN Connector LEDs 
LED  LED Color  LED State  Indicates 
A  Off  LAN link is not established 
 
Green 
On  LAN link is established 
  Blinking LAN activity is occurring 
N/A  Off  10 Mb/s data rate 
Green  On   100 Mb/s data rate 
B 
Yellow  On  1000 Mb/s data rate