Has anyone messed with the Extreme OV option?

I recently Enabled it and noticed some extra settings appear: QPI, IOH, DRAM Voltage OCP and QPI, IOH, and DRAM PWM Frequency. Does anyone know what the settings for PWM Frequency mean? They are AUTO, 1x, 1.33x. Are the settings in relation to CPU PWM Frequency?

I have recently seen users mentioning they use a lower setting for CPU PWM Frequency so I thought I'd lower PWM Freq. for QPI, IOH, and DRAM also.