I try what you said and nothing...
sudo lspci -nnk | grep -iA3 net
About live CD, I tested both versions 32b and 64b for 12.04.3 in live mode, and network problem didnt change.
00:07.0 Bridge : NVIDIA Corporation MCP61 Ethernet [10de:03ef] (rev a2)
Subsystem: ASRock Incorporation 939NF6G-VSTA Board [1849:03ef]
Kernel driver in use: forcedeth
Kernel modules: forcedeth
I bought this machine a month ago and I can't use it yet. Also there is another issue with power, it do not shutdown or restart by it self, I have to press the buttons for both actions.
About motherbiard as far as I know it only has one interface.
Anyway thanks again for your time and advice.