Manual
Table Of Contents
- P7P55D-E Premium specifications summary
- About this guide
- Safety information
- Notices
- Chapter 1: Product introduction
- Chapter 2: Hardware information
- Chapter 3: BIOS setup
- 3.1 Knowing BIOS
- 3.2 Updating BIOS
- 3.3 BIOS setup program
- 3.4 Main menu
- 3.5 Ai Tweaker menu
- 3.5.1 Ai Overclock Tuner [Auto]
- 3.5.2 CPU Ratio Setting [Auto]
- 3.5.3 Intel(R) SpeedStep(TM) Tech [Enabled]
- 3.5.4 Intel(R) TurboMode Tech [Enabled]
- 3.5.5 Xtreme Phase Full Power Mode [Auto]
- 3.5.6 DRAM Frequency [Auto]
- 3.5.7 QPI Frequency [Auto]
- 3.5.8. DRAM Timing Control [Auto]
- 3.5.9 CPU Differential Amplitude [Auto]
- 3.5.10 CPU Clock Skew [Auto]
- 3.5.11 CPU Voltage Mode [Offset]
- 3.5.12 IMC Voltage [Auto]
- 3.5.13 DRAM Voltage [Auto]
- 3.5.14 CPU PLL Voltage [Auto]
- 3.5.15 PCH Voltage [Auto]
- 3.5.16 DRAM DATA REF Voltage on CHA/B [Auto]
- 3.5.17 DRAM CTRL REF Voltage on CHA/B [Auto]
- 3.5.18 Load-Line Calibration [Auto]
- 3.5.19 CPU Spread Spectrum [Auto]
- 3.5.20 PCIE Spread Spectrum [Auto]
- 3.6 Advanced menu
- 3.7 Power menu
- 3.8 Boot menu
- 3.9 Tools menu
- 3.10 Exit menu
- Chapter 4: Software support
- Chapter 5: Multiple GPU technology support

2-26 Chapter 2: Hardware information
Chapter 2
4. CPU / IMC / DRAM overvoltage setting switches (OV_DRAM, OV_IMC, OV_CPU)
These switches allow you to enable or disable the advanced CPU, Integrated Memory
Controller (IMC), and DRAM overvoltage settings in BIOS. Read the following
information before you change the switch settings.
• Before you change the switch settings for extra-high overvoltage ability, use the BIOS
items rst to adjust the desired CPU, IMC, and DRAM performance. Ensure your
system functions well under the highest BIOS voltage settings before you change the
setting of these three switches.
• DO NOT enable the OV_CPU switch when you install a new CPU and have not
booted for the rst time. Doing so may cause the system to halt. For system failure
due to the wrong setting of the OV_CPU switch, shut down the computer and set the
switch back to its default position.
• According to Intel CPU spec, DIMMs voltage below 1.65V is recommended to protect
the CPU.
• The system may need a better cooling system (for example, a water-cooling system)
to work stably under high voltage settings.
OV_CPU OV_IMC OV_DRAM
Default 0.85V to 1.7V up to 1.7V up to 2.0V
Enable OV (red) 1.25V to 2.1V up to 1.9V up to 2.5V
The LED color indicates the voltage setting status of CPU, IMC and DRAM.