Intel Quad-core Intel Xeon DP L5335 Active BX80563L5335A Data Sheet

Product codes
BX80563L5335A
Page of 124
Features
110
Quad-Core Intel® Xeon® Processor 5300 Series Datasheet
support this feature will be provided in future releases of the Quad-Core Intel® Xeon® 
Processor 5300 Series NDA Specification Update when available.
Enhanced Intel SpeedStep Technology creates processor performance states (P-states) 
or voltage/frequency operating points. P-states are lower power capability states within 
the Normal state as shown in 
. Enhanced Intel SpeedStep Technology 
enables real-time dynamic switching between frequency and voltage points. It alters 
the performance of the processor by changing the bus to core frequency ratio and 
voltage. This allows the processor to run at different core frequencies and voltages to 
best serve the performance and power requirements of the processor and system. The 
Quad-Core Intel® Xeon® Processor 5300 Series have hardware logic that coordinates 
the requested voltage (VID) between the processor cores. The highest voltage that is 
requested from the four processor cores is selected for that processor package. Note 
that the front side bus is not altered; only the internal core frequency is changed. In 
order to run at reduced power consumption, the voltage is altered in step with the bus 
ratio.
The following are key features of Enhanced Intel SpeedStep Technology:
• Multiple voltage/frequency operating points provide optimal performance at 
reduced power consumption.
• Voltage/frequency selection is software controlled by writing to processor MSR’s 
(Model Specific Registers), thus eliminating chipset dependency.
— If the target frequency is higher than the current frequency, V
CC
 is incremented 
in steps (+12.5 mV) by placing a new value on the VID signals and the 
processor shifts to the new frequency. Note that the top frequency for the 
processor can not be exceeded.
— If the target frequency is lower than the current frequency, the processor shifts 
to the new frequency and V
CC
 is then decremented in steps (-12.5 mV) by 
changing the target VID through the VID signals.
See the Conroe and Woodcrest Processor Family BIOS Writer’s Guide for specific 
information to enable and configure Enhanced Intel SpeedStep Technology in BIOS.
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