X-bit labs

Getting Ready to Meet Intel Core 2 Duo: Core Microarchitecture Unleashed (page 8)

Category: CPU

by Ilya Gavrichenkov

[ 06/29/2006 | 05:13 PM ]

Intel Intelligent Power Capability

When working on new Core Microarchitecture, Intel engineers tried to maximally optimize the “performance per watt” parameter. Besides, this microarchitecture is also designed for notebook processors, so the developers paid special attention to the technologies that would allow reducing the heat dissipation and power consumption of the upcoming CPUs. Of course, the new processors will have at their disposal such technologies as Demand Based Switching (primarily, Enhanced Intel SpeedStep and Enhanced Halt State). However, we are not going to talk about them here.

The CPUs based on Core microarchitecture will be able to interactively disable their subsystems that are not being used at the given moment. And we are not talking about the whole core here. The processor is decomposed into much lower-level units. Each of the processor cores is split into a lot of units and internal busses, which are powered separately with the help of additional logic circuits. The main peculiarity of the circuits within Intel Intelligent Power Capability is the fact that they do not cause any increase in the CPU response time to external influences when its needs to reactivate previously disabled units.

Note that the possibility to deactivate different CPU units on the fly pushed the developers to revise the way the processor temperature was measured. CPUs based on Core Microarchitecture will be equipped with a few thermal diodes on the core close to those spots that tend to heat most. To process all this thermal data the CPU will be equipped with a special circuitry that will determine the highest temperature. The CPU will report this particular temperature value to the user and hardware monitoring systems.