Frequency/Voltage Control - MSI 648M-IL User Manual

BIOS Setup

Frequency/Voltage Control

Use this menu to specify your settings for frequency/voltage control.
CPU Clock Ratio
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 DIMM/PCI Clk
This option allows you to enable/disable the feature of auto detecting the clock
frequency of the installed DIMM/PCI bus. The settings are: 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.
Options: Disabled, +/-0.25%, +/-0.30%, +/-0.35%, +/-0.40%.
CPU Frequency
Use this item to select the appropriate frequency for your CPU FSB. Options
are: Default, 100MHz, 133MHz.
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