MSI AM-690E User Manual page 55

Onboard Peripherals Configuration
Spread Spectrum
When the motherboard's clock generator pulses, the extreme values (spikes)
of the pulses create EMI (Electromagnetic Interference). The Spread Spectrum
function reduces the EMI generated by modulating the pulses so that the spikes
of the pulses are reduced to flatter curves.
Important
1. 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,
select the value of Spread Spectrum for EMI reduction.
2. The greater the Spread Spectrum value is, the greater the EMI is reduced,
and the system will become less stable. For the most suitable Spread
Spectrum value, please consult your local EMI regulation.
3. Remember to disable Spread Spectrum if you are overclocking because
even a slight jitter can introduce a temporary boost in clock speed which
may just cause your overclocked processor to lock up.
Onboard LAN Boot ROM
The setting enables/disables the initialization of the onboard LAN Boot ROM
during bootup. Selecting [Disabled] will speed up the boot process.
BIOS Setup
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