Intel 2 Duo T5600 LE80537GF0342M User Manual

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Datasheet

The Intel Core 2 Duo mobile processor features Enhanced Intel SpeedStep Technology. 

Following are the key features of Enhanced Intel SpeedStep Technology:

• Multiple voltage and frequency operating points provide optimal performance at the 

lowest power. 

• Voltage and frequency selection is software controlled by writing to processor 

MSRs:

— . If the target frequency is higher than the current frequency, Vcc is ramped up 

in steps by placing new values on the VID pins and the PLL then locks to the 

new frequency.

— If the target frequency is lower than the current frequency, the PLL locks to the 

new frequency and the V

CC

 is changed through the VID pin mechanism.

— Software transitions are accepted at any time. If a previous transition is in 

progress, the new transition is deferred until the previous transition completes.

• The processor controls voltage ramp rates internally to ensure glitch free 

transitions.

• Low transition latency and large number of transitions possible per second:

— Processor core (including L2 cache) is unavailable for up to 10 μs during the 

frequency transition.

— The bus protocol (BNR# mechanism) is used to block snooping.

• Improved Intel Thermal Monitor mode:

— When the on-die thermal sensor indicates that the die temperature is too high, 

the processor can automatically perform a transition to a lower frequency and 

voltage specified in a software programmable MSR.

— The processor waits for a fixed time period. If the die temperature is down to 

acceptable levels, an up transition to the previous frequency and voltage point 

occurs.

— An interrupt is generated for the up and down Intel Thermal Monitor transitions 

enabling better system level thermal management. 

• Enhanced thermal management features.

— Digital Thermal Sensor and Out of Specification detection.
— Intel Thermal Monitor 1 in addition to Intel Thermal Monitor 2 in case of 

unsuccessful Intel Thermal Monitor 2 transition.

— Dual-core thermal management synchronization. 

Each core in the processor implements an independent MSR for controlling Enhanced 

Intel SpeedStep Technology, but both cores must operate at the same frequency and 

voltage. The processor has performance state coordination logic to resolve frequency 

and voltage requests from the two cores into a single frequency and voltage request for 

the package as a whole. If both cores request the same frequency and voltage, then 

the processor will transition to the requested common frequency and voltage. If the 

two cores have different frequency and voltage requests, then the processor will take 

the highest of the two frequencies and voltages as the resolved request and transition 

to that frequency and voltage.