No, when I say auto, I mean I can't change anything - the mobo/programs manage the voltage by itself. I don't mean an "auto/manual" option bar.
Again, the 5%, 10%, 15% is not changing the actual base CPU voltage, but only deals with cpu overvoltage. Since I don't know what the base CPU voltage value is, I have no idea what percentage will be changed if I use the overvoltage option.
I did try to guess-and-test it with auto-overvoltage, 5% overvoltage, 10% overvoltage, but the numbers didn't seem to make a difference when I checked CPU-z
I have to say that the 45nm e7200 is one of the best overclockers... i got mine running at 4.03 1700 FSB on air using a freezer 7 pro and a biostar TP35D2A7 idles 42 load 63 which is well under the 75C ( voltage is a little high but teps are fne so i don't worry about it