Step 4 : Adjust Voltages CPU voltage settings displayed below :
CPU Vcore : For extreme cooling ( LN2 ) you ’ re aiming for 1.85-1.90V to max out your CPU . There are CPUs that can obtain higher frequencies using higher voltages but 1.85V is a good starting point .
CPU VCCIO and CPU System Agent : These settings will mainly aid you in memory overclocking . A setting of up to 1.4V on both maxes out most DRAM . We suggest you start slowly from 1.3V on both and find the optimum value for your DRAM / CPU .
VCC Substained : Set this to 1.45-1.55V . Start from 1.45V and check if your CPU needs more . If you ’ re getting random freezes at high clocks raise it to a higher value .
VCCPLL : Make sure you have iGPU disabled before you do this as it might kill your iGPU otherwise . Make sure you are using a discrete graphics cards . 1.8V should eliminate CB in a CPU . From our experience you don ’ t need higher than that . If you ’ re limited only to 1.5V then you need an X version bios ( available in “ Overclocking Software ” section ).
VCCPLL OC : You ’ re looking at values around 2.0V . It helps if you ’ re hitting the CB earlier than you should ( -130C or so ). Some CPUs need higher but 2.0V is a good starting value . Keep this value under 3.0V or you might degrade your CPU .
VCCVTT : 1.65V should work well for most of the CPUs . If you ’ re getting random freezes at high clocks try to raise it . Keep this under 1.75V or damage could be done to your CPU even when using LN2 .
VCCDMI _ PEG : This setting is used to stabilize your 3D VGA performance . We always set it at 1.4V and then raise it when it ’ s needed . Depending on how your VGA behaves , up to 1.85V is fine . Make sure you raise VCCIO along with VCCDMI _ PEG , set VCCIO anywhere from 1.25V to 1.4V otherwise your CPU might not boot .