While in active states, the processor and the operating system jointly decide frequencies for
various parts of the system (CPUs, GPU, and memory ring, in particular). The current
generation of Intel Core processors add more interaction between the operating system and the
processor(s) to respond more efficiently and quickly to changes in power demand—a process
referred to as Intel® Speed Shift Technology.
The system balances the frequencies based on activity and increases frequency (and thus
consumed power) where it is needed most. As a result, a mostly active workload may have its
GPU and CPU balance frequencies based on power consumption.
Reducing the amount of work done on the CPU can free up power for the GPU and vice versa.
This can result in better overall performance, even when the other side was the primary
Tools such as Intel® Power Gadget
can also help you see the
frequencies of each clock domain in real time. You can monitor the frequencies of different
subsystems on target devices by running this tool.
You can tell that your app’s power distribution is getting balanced when the primary
performance bottleneck is not running at full frequency, but power consumption is reaching the
maximum limits available.