I recently upgraded Ubuntu 12.04 to 12.10 only to find out that it won't connect to any network, neither wired nor wireless and the graphics is messed up too as in a low screen resolution.

For 12.04, my system was running perfectly. I don't know why upgrade messed it up so bad. Reinstalling the OS is an issue because I have set up a lot of development environments that I cannot afford to set it up again.

Some of the outputs:

lspci -nn | grep 0200
02:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8101E/RTL8102E PCI Express Fast Ethernet controller [10ec:8136] (rev 02)

nm-tool

NetworkManager Tool

State: disconnected

cat /etc/network/interfaces
auto lo
iface lo inet loopback

sudo cat /var/log/syslog | grep etwork | tail -n20
Nov  2 13:50:22 Cobalt NetworkManager[978]:    SCPlugin-Ifupdown: (-1240454760) ... get_connections (managed=false): return empty list.
Nov  2 13:50:22 Cobalt NetworkManager[978]:    Ifupdown: get unmanaged devices count: 0
Nov  2 13:50:22 Cobalt bluetoothd[1016]: Failed to init network plugin
Nov  2 13:50:22 Cobalt NetworkManager[978]: <info> modem-manager is now available
Nov  2 13:50:22 Cobalt NetworkManager[978]: <info> monitoring kernel firmware directory '/lib/firmware'.
Nov  2 13:50:22 Cobalt NetworkManager[978]: <info> WiFi enabled by radio killswitch; enabled by state file
Nov  2 13:50:22 Cobalt NetworkManager[978]: <info> WWAN enabled by radio killswitch; enabled by state file
Nov  2 13:50:22 Cobalt NetworkManager[978]: <info> WiMAX enabled by radio killswitch; enabled by state file
Nov  2 13:50:22 Cobalt NetworkManager[978]: <info> Networking is enabled by state file
Nov  2 13:50:22 Cobalt NetworkManager[978]: <warn> /sys/devices/virtual/net/lo: couldn't determine device driver; ignoring...
Nov  2 13:50:22 Cobalt NetworkManager[978]: <warn> /sys/devices/virtual/net/lo: couldn't determine device driver; ignoring...
Nov  2 13:50:22 Cobalt NetworkManager[978]: <warn> bluez error getting default adapter: Message did not receive a reply (timeout by message bus)
Nov  2 13:50:22 Cobalt NetworkManager[978]: <warn> bluez error getting default adapter: Message did not receive a reply (timeout by message bus)
Nov  2 13:50:22 Cobalt kernel: [   28.688167] type=1400 audit(1351882222.452:10): apparmor="STATUS" operation="profile_replace" name="/usr/lib/NetworkManager/nm-dhcp-client.action" pid=1046 comm="apparmor_parser"
Nov  2 13:50:22 Cobalt bluetoothd[1062]: Failed to init network plugin
Nov  2 13:50:22 Cobalt NetworkManager[978]: <warn> bluez error getting default adapter: Message did not receive a reply (timeout by message bus)
Nov  2 13:50:22 Cobalt bluetoothd[1118]: Failed to init network plugin
Nov  2 13:50:22 Cobalt NetworkManager[978]: <warn> bluez error getting default adapter: Message did not receive a reply (timeout by message bus)
Nov  2 13:50:22 Cobalt bluetoothd[1237]: Failed to init network plugin
Nov  2 13:50:22 Cobalt NetworkManager[978]: <warn> bluez error getting default adapter: Message did not receive a reply (timeout by message bus)

ps aux | grep -i network
root       978  0.0  0.1  23732  4808 ?        Ssl  13:50   0:00 NetworkManager

sudo modprobe -r forcedeth
FATAL: Module forcedeth not found