Intel Core 2 Duo E7300 BX80570E7300 User Manual

Thermal and Mechanical Design Guidelines   

 33 

An increase in processor operating frequency not only increases system performance, 

but also increases the processor power dissipation. The relationship between 

frequency and power is generalized in the following equation: P = CV

2

F  

(where P = power, C = capacitance, V = voltage, F = frequency). From this equation, 

it is evident that power increases linearly with frequency and with the square of 

voltage. In the absence of power saving technologies, ever increasing frequencies will 

result in processors with power dissipations in the hundreds of watts. Fortunately, 

there are numerous ways to reduce the power consumption of a processor, and Intel 

is aggressively pursuing low power design techniques. For example, decreasing the 

operating voltage, reducing unnecessary transistor activity, and using more power 

efficient circuits can significantly reduce processor power consumption. 

An on-die thermal management feature called Thermal Monitor is available on the 

processor. It provides a thermal management approach to support the continued 

increases in processor frequency and performance. By using a highly accurate on-die 

temperature sensing circuit and a fast acting Thermal Control Circuit (TCC), the 

processor can rapidly initiate thermal management control. The Thermal Monitor can 

reduce cooling solution cost, by allowing thermal designs to target TDP.  

The processor also supports an additional power reduction capability known as 
Thermal Monitor 2 described in Section 

4.2.3.  

The Thermal Monitor consists of the following components:  

 

A highly accurate on-die temperature sensing circuit  

 

A bi-directional signal (PROCHOT#) that indicates if the processor has exceeded 

its maximum temperature or can be asserted externally to activate the Thermal 
Control Circuit (TCC) (see Section 

using the PROCHOT# signal) 

 

A Thermal Control Circuit that will attempt to reduce processor temperature by 

rapidly reducing power consumption when the on-die temperature sensor indicates 

that it has exceeded the maximum operating point. 

 

Registers to determine the processor thermal status.