at the top of your board beside dimm slot 1 and just under the cpu fan header is a jumper 1/2=3.3 volts 2/3= 3.6 volts.
when you first boot you will have to enter bios and change your monitoring as it will now see an overvoltage and not boot. then change the asus probe monitor to allow a 15% variance on i/o voltage or probe will report overvoltage