Thanks. Install the new driver as you suggested.
Same thing happens. After the new driver installed, the network worked for 5 minutes, then the LED lights were off, and no network.
If I disconnect the powercord from the computer (NOT just shut down) and reboot again, then the network works for ~5 mins, then no connection again.
You could try to reinstall the Lan driver from Asus, Version 5.796&7.61 Realtek Lan Driver. Also you should do a diagnogsotic test of your router.