okay, when you disable "D.O.T. Control" in the cell menu, you still cant select the cpu voltage?
if you hit "enter", nothing happens?
what about if you use the +/- keys? or try just enetering the voltage manually, like "1.4 > enter"
like, highlight the cpu voltage in red and type 1.4 and hit enter. make sure to save your change if that works.
that has to be disabled to enable user definition of voltages. and if it is didabled, you should be able to change it.