I use the REALTEK RTL8211 chip to transmit video streaming data, work in gigabit mode,
In use process found a problem:
1, the two pieces of the same circuit board, the board has RTL8211 gigabit front-end ports, after connecting, both cannot be established stable connection, link and then go out, when the indicator lamp light cycle, two connected RTL8211 RXCLK in 2.5 M, 25 M, 125 M between jump,

2, any RTL8211 gigabit front-end ports connected to the computer so, link building success, and stable, link light is normally on,
This is what causes, how to solve