Frequency/Voltage Control - MSI MS-6555 Manual

Chapter 3

Frequency/Voltage Control

This section controls the frequency/voltage of the CPU and certain onboard
hardware to enhance overall system performance.
CPU Ratio Selection
This setting controls the multiplier that is used to determine the internal clock
speed of the processor relative to the external or motherboard clock speed.
Auto Detect PCI Clock
This item is used to auto detect the PCI slots. When set to Enabled, the system
will remove (turn off) clocks from empty PCI slots to minimize the electromag-
netic interference (EMI). Setting options: Enabled, Disabled.
Spread Spectrum
When the motherboard's clock generator pulses, the extreme values (spikes)
of the pulses creates EMI (Electromagnetic Interference). The Spread Spec-
trum function reduces the EMI generated by modulating the pulses so that the
spikes of the pulses are reduced to flatter curves. If you do not have any EMI
problem, leave the setting at Disabled for optimal system stability and
performance. But if you are plagued by EMI, activate the Spread Spectrum for
EMI reduction. Remember to disable Spread Spectrum if you are overclocking
because even a slight jitter can introduce a temporary boost in clockspeed
which may just cause your overclocked processor to lock up.
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