sudo apt-get gnome-device-manager
To access it just go to Applications -> System Tools -> Device Manager
Using the command line you can list your hardware this way:
sudo lshw | more
sudo lshw -C memory | more or sudo lshw -C cpu | more
Reference:
Install Device Manager
http://www.brighthub.com/computing/linux/articles/41828.aspx
lshw Command
http://manpages.ubuntu.com/manpages/lucid/man1/lshw.1.html