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P67A-GD55 manual:
CPU Vcore/ CPU IO/ DRAM Voltage/ CPU SA/ CPU PLL Voltage/ DDR_VREF_CA_A/
DDR_VREF_CA_B/ DDR_VREF_DA_A/ DDR_VREF_DA_B/ PCH 1.05
These items are used to adjust the voltage of CPU, Memory and chipset.
P67A-C45 manual:
CPU Vcore/ DRAM Voltage/ PCH 1.05
These items are used to adjust the voltage of CPU, Memory and chipset.