Testing the HDMI port with an external monitor in ChromeOS and Chr-Ubuntu
I took my Chromebook to work and tested the HDMI-out port with my employer's BenQ GW2750.
First, here is ChromeOS.
Next, here is Ubuntu 13.10
The ChromeOS interface is much easier to use. Just select your primary monitor and the pointer will appear on that monitor and you are good to go. In Ubuntu it is a bit wonky--you have to play with it a little to achieve the desired result (i.e. get your pointer active in the external monitor).