Intel i3-4360T CM8064601481958 User Manual

A software readable field in the TEMPERATURE_TARGET register contains the

minimum temperature at which the TCC will be activated and PROCHOT# will be

asserted. The TCC activation temperature is calibrated on a part-by-part basis and

normal factory variation may result in the actual TCC activation temperature being

higher than the value listed in the register. TCC activation temperatures may change

based on processor stepping, frequency or manufacturing efficiencies.

The Adaptive Thermal Monitor feature provides an enhanced method for controlling

the processor temperature when the processor silicon exceeds the Thermal Control

Circuit (TCC) activation temperature. Adaptive Thermal Monitor uses TCC activation to

reduce processor power using a combination of methods. The first method (Frequency

control, similar to Thermal Monitor 2 (TM2) in previous generation processors)

involves the processor reducing its operating frequency (using the core ratio

multiplier) and internal core voltage. This combination of lower frequency and core

voltage results in a reduction of the processor power consumption. The second

method (clock modulation, known as Thermal Monitor 1 or TM1 in previous generation

processors) reduces power consumption by modulating (starting and stopping) the

internal processor core clocks. The processor intelligently selects the appropriate TCC

method to use on a dynamic basis. BIOS is not required to select a specific method

(as with previous-generation processors supporting TM1 or TM2). The temperature at

which Adaptive Thermal Monitor activates the Thermal Control Circuit is factory

calibrated and is not user configurable. Snooping and interrupt processing are

performed in the normal manner while the TCC is active.

When the TCC activation temperature is reached, the processor will initiate TM2 in

attempt to reduce its temperature. If TM2 is unable to reduce the processor

temperature, TM1 will be also be activated. TM1 and TM2 will work together (clocks

will be modulated at the lowest frequency ratio) to reduce power dissipation and

temperature.

With a properly designed and characterized thermal solution, it is anticipated that the

TCC will only be activated for very short periods of time when running the most power

intensive applications. The processor performance impact due to these brief periods of

TCC activation is expected to be so minor that it would be immeasurable. An under-

designed thermal solution that is not able to prevent excessive activation of the TCC in

the anticipated ambient environment may cause a noticeable performance loss, and in

some cases may result in a T

CASE

 that exceeds the specified maximum temperature

and may affect the long-term reliability of the processor. In addition, a thermal

solution that is significantly under designed may not be capable of cooling the

processor even when the TCC is active continuously. See the appropriate processor

Thermal Mechanical Design Guidelines for information on designing a compliant

thermal solution.

The Thermal Monitor does not require any additional hardware, software drivers, or

interrupt handling routines. The following sections provide more details on the

different TCC mechanisms used by the processor.

Desktop 4th Generation Intel

®

 Core

™

 Processor Family, Desktop Intel

®

 Pentium

®

 Processor Family, and Desktop Intel

®

 Celeron

®

Processor Family

Datasheet – Volume 1 of 2

July 2014

78

Order No.: 328897-009