The Kubuntu live CD could provide valuable driver information. When you next run it, do 'lsmod' and cut/paste the results to text file. That will tell you what ethernet and sound drivers are loaded. Also, do 'lspci' (as root). Post the info (save on a memory stick if you need to).

Now, one potential issue I'm aware of (not sure if it applies to you) regarding this nvidia chipset, is that after booting into windows, the network hardware can require being discharged before being able to be activated in linux; (turn off the computer and unplug the power cord then when repowered up the ethernet will work on Linux). This has been mentioned before.