I have a PC with an Intel motherboard (model: dg41rq). I have a Linux CD that I run as a live cd. when the Linux is booted, I have no network connection. The stranger issue is that after I restart my computer and boot up windows (server 2003), I have no network connection in windows too! when I looked in the device manager, no network card was identified. the only way to fix the problem is to shut down the computer and disconnect it's power source, wait a few minutes, and then boot windows again.
I found a similar problem in another Intel motherboard: