Windows Server 2008 R2, a new step forward in power management
In this day and age, power use is on everyone's mind. Windows Server 2008 R2 helps reduce and optimize power usage in most, if not all, situations; in all cases, savings can be achieved and realized simply by installing the operating system.
Perhaps the easiest savings to point to when upgrading to Windows Server 2008 R2 is in power management. In essence, on the same hardware with the same load factors, Microsoft claims R2 will present anywhere from 10% to 15% -- and sometimes even 18% -- power savings over Windows Server 2003 with Service Pack 2, without requiring any additional configuration.
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Core parking is another interesting feature that intelligently detects loads on a system and prioritizes and optimizes the distribution of that processing workload among all of the cores available to the operating system. For instance, on single quad-core processor, core parking will enable modest workloads to be carried out only on one core and allow the remaining three cores to remain in a power-saving inactive state. When workloads become heavy enough to require the use of other cores, the OS "lights up" the other cores as necessary to handle the duties, and then returns them to the inactive state -- creating, in other words, a "bursting" of processor capacity.
the full article is here : http://www.computerworld.com/s/article/9135816/Review_Windows_Server_2008_R2_RTM?taxonomyId=154&pageNumber=3
