GIGABYTE Z270 Overclocking Guide GIGABYTE 200 Series Overclocking Guide - Page 26

For PCI-E 2.0 2D and 3D benchmarks set it to a value of at least 1.4V to avoid CB . If you ’ re using a PCI-e 3.0 VGA then you can choose to use Nvidia PowerMizer Manager ( nvpm manager ) or in the BIOS set a high VCCDMI _ PEG ( 1.8V +).
If you ’ re using a PCI-E slot from PCH then VCCDMI _ PEG doesn ’ t affect that slot .
CPU Core PLL Overvoltage (+ mV ): This setting depends on your CPU . Start without it and try to raise it to see if it helps your CPU . Values up to 285mV work ok on LN2 . ( Default value is 0.9V )
PCH Core : You should raise this setting together with VCCVTT . We always set it at 1.12- 1.14V . If your system reboots and it goes to code C5 with a blank debug LED then raise this value .
CPU Vcore Loadline Calibration : Even though “ Turbo ” should work just fine we prefer to set it at “ Extreme ” just to be safe .
Just to be safe we prefer to always make 2 profiles . The first one is without these voltage settings and the second one is with them . We then cool the CPU down to -70C or so and then load the second profile .