What OS ? Win7 is more or less dummy proof when it comes to connectivity.
Install your mobo drivers from Asus CD again.
Plug ethernet cable in pc directly from your isp modem.
Removing routers etc,from the link.
I have similar problem. Hopefully somebody knows the answer.
When I restart or startup within 3 minutes of shutdown the Realtek network adapter is not found (ever).
Most times if I wait > 5 minutes it finds, add driver and runs ok.
I'm installing the drivers to my motherboard and when I get to the LAN I get this error
"The RealTek Network Adapter/Controller was not found.
If Deep Sleep Mode enabled Please Plug the Cable"
I'm not sure what's going on here. I go to device manager and no network shows up. Am I missing something? Was there something I should of connected to the motherboard that I didn't connect?
Motherboard: ASUS P7P55d-e Pro
Realtek RTL8111B/C & RTL8112L 10/100/1000M LAN Driver V7.3.522.2009
Also check your power management features
sounds like you don't have settings done properly
power plan etc
performance is the best setting btw
change advanced settings
multitude of tab settings.