pi_overclock.txt

Stock profile:
self.normal_profile = self.oc_profile(700, 400, 250, 0, 0, 0, 0)

Normal profile:
self.normal_profile = self.oc_profile(850, 400, 375, 0, 0, 0, 0)

Medium profile: mild overclock settings.
self.medium_profile = self.oc_profile(900, 400, 375, 0, 0, 0, 0)

High profile: higher overclock settings.
self.higher_profile = self.oc_profile(950, 450, 450, 0, 6, 0, 0)

Custom profile:
self.custom_profile = self.oc_profile(arm_freq, sdram_freq, core_freq, initial_turbo, over_voltage, over_voltage_sdram, force_turbo)

arm_freq

Frequency of ARM (cpu) in MHz.

sdram_freq

Frequency of SDRAM in MHz.

core_freq

Frequency of GPU processor core in MHz.
It has an impact on ARM performance since it drives L2 cache.
Also, note that SD card issues are usually affected by the core_freq, rather than the arm_freq.

initial_turbo

Enables turbo mode from boot for the given value in seconds (up to 60) or until cpu_freq sets a frequency.

over_voltage

ARM/GPU core voltage adjust. [-16,8] equates to [0.8 V,1.4 V] with 0.025 V steps.
Values above 6 are only allowed when force_turbo or current_limit_override are specified (which voids the warranty).

over_voltage_sdram

Sets over_voltage_sdram_c, over_voltage_sdram_i, over_voltage_sdram_p together.

force_turbo

Disables dynamic cpufreq driver and minimum settings below.
Enables H.264/V3D/ISP overclock options.
May void the warranty.