Intel E5-1660 CM8062107284111 User Manual

Product codes
CM8062107284111
Page of 258
Intel® Xeon® Processor E5-1600/E5-2600/E5-4600 Product Families
139
Datasheet Volume One
5.2.2.1
Frequency/SVID Control
The processor uses Frequency/SVID control whereby TCC activation causes the 
processor to adjust its operating frequency (via the core ratio multiplier) and VCC input 
voltage (via the SVID signals). This combination of reduced frequency and voltage 
results in a reduction to the processor power consumption.
This method includes multiple operating points, each consisting of a specific operating 
frequency and voltage. The first operating point represents the normal operating 
condition for the processor. The remaining points consist of both lower operating 
frequencies and voltages. When the TCC is activated, the processor automatically 
transitions to the new lower operating frequency. This transition occurs very rapidly (on 
the order of microseconds).Once the new operating frequency is engaged, the 
processor will transition to the new core operating voltage by issuing a new SVID code 
to the VCC voltage regulator. The voltage regulator must support dynamic SVID steps 
to support this method. During the voltage change, it will be necessary to transition 
through multiple SVID codes to reach the target operating voltage. Each step will be 
one SVID table entry (see 
). The processor continues to execute instructions 
during the voltage transition. Operation at the lower voltages reduces the power 
consumption of the processor.
A small amount of hysteresis has been included to prevent rapid active/inactive 
transitions of the TCC when the processor temperature is near its maximum operating 
temperature. Once the temperature has dropped below the maximum operating 
temperature, and the hysteresis timer has expired, the operating frequency and 
voltage transition back to the normal system operating point via the intermediate 
SVID/frequency points. Transition of the SVID code will occur first, to insure proper 
operation once the processor reaches its normal operating frequency. Refer to 
 for an illustration of this ordering.
Figure 5-33. Frequency and Voltage Ordering