Granola is a free utility for Linux or Windows which can reduce the power consumption by your computers by optimizing the CPU power usage.
When your computer is working hard (for instance, when you are playing a game) the CPU needs to be at full speed so that it can work effectively. When your computer is "relaxing" (for instance, when you are browsing a web site) your CPU can "dim" itself by slowing down execution without you noticing. In the lower state, the CPU consumes less energy, thus making your computer more efficient. If you wanted to, you could switch between the "bright" and "dim" modes yourself to match your usage. In order to get the most efficient use of power in your computer system though, you would need to switch DVFS modes every time you changed your usage.
Energy savings without compromising performance and availability
Supports x86 platforms running Linux and Microsoft Windows on physical/virtual servers
Immediate energy saving for most deployments <5 years old
User-level max, min, and auto energy and performance policy management
User-level reporting of energy savings without additional hardware required
No measurable overhead (<1%).
Energy savings and software complimentary to consolidation techniques such as virtualization
Installation takes less than 5 minutes on average
Little to no maintenance
This software is free for Personal Use.
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