If you are deploying Windows Server 2012 R2 and want to get the most out of your existing hardware, this white paper is for you:
http://msdn.microsoft.com/en-us/library/windows/hardware/dn529133.aspx
Under one single repository you will find all the registry keys, tools and tips to make your Windows Server 2012 R2 perform at its best!
It does not necessarily mean that the server will improve its performance but it may consume the lowest energy for a give performance rate. By following the guidelines that comes in this white paper, you will obtain performance or energy efficiency gains. The settings that are recommended in this document should be take carefully and always have in considerations what hardware you are using, and your datacenter environment.
It also describes each setting and its potential effect to help you make an informed decision about its relevance to your system, workload, performance, and energy usage goals.