its very easy, my undervolt settings are the ones here on apexs kernal http://www.droidforums.net/forum/fa...k-apex-kernel-v4-12-23-11-charging-fixed.html, and my underclock\overclock is at 350mhz to 1350mhz, 1420 doesnt work for me, and 350mhz when screen off, set at interactivex scaling setting, i have used 180mhz on lean kernel but i havent seen a difference with it and 350mhz. good luck