Acer Veriton Z290G Service Manual page 27

Frequency/Voltage Control
Field
Spread Spectrum
Processor Multiplier
Veriton Z290G Service Guide
Description
When the mainboard's clock generator pulses, the extreme values of
the pulses creates EMI (electromagnetic interference). Set this field
to Enabled to reduce this EMI level. This reduces interference
problems with other electronics in the area.
Note: Remember to disable the Spread Spectrum feature if you are
overclocking. A slight jitter can introduce a temporary boost in clock
speed causing the overclocked processor to lock up.
This field is only visible if an engineering processor installed. It is only accessible
when the EIST function is disabled.
Value
Enabled
Disabled
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