I see. I have also seen some information from somewhere that the graphic card could be disabled to save more power. Since we may use putty or IE to work with the Asterisk server.
Also we may use CF card as the system or using notebook hard drive to save more power too.
I think the info you got is just the power consumption for ATOM cpu. The integrated graphics card has larger power consumption. If some linux gurus could switch off the graphics card, it definitely gains 8~9Watts
I measured the total power consumption direct from the input to the PSU. The PSU should take a few Watts(?), hadrdisk a few Watts, (something more?). Hence it does agree with 30W.