MSI Q35MDO v2 Manual page 56

Disabled for optimal system stability and performance. But if you are plagued by EMI,
set to Enabled for EMI reduction. 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.
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.
BIOS Setup
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