I am using Ubuntu 13.04 64-bit. I need to perform some database benchmarks on my computer so I want to make it in strict terminal mode, without desktop. I know I can ctrl-alt-f1 to go to terminal mode, but there is still graphical desktop running in background. (Using CPU and RAM which I do not want it to).

So please help me to kill all graphical components and switch to only terminal mode (for better performance). I will not need multiple users to be able to log in and do not need to have networking (all benchmarks will be on localhost interface).