Core parking is a new feature that Microsoft introduced in Windows 7 and Windows Server 2008 R2. Depending on the resource use of the operating system it may park one or multiple cores of a multi-core CPU to reduce the computer's power consumption and thermal emissions. Once operations require more processing power, the parked cores are activated again to assist in the tasks.
Especially mobile users benefit from core parking, while desktop users may benefit from it indirectly on their utility bill. For some multi-core processors, core parking is not enabled by default, and if you want to enable the feature you will be hard pressed to find any tools or information that allow you to do that.
Users with AMD processors on the other hand may experience less than optimal processing powers while core parking is enabled on their system. You may remember that this was a issue some time ago. Microsoft has released a hotfix for AMD users that disables core parking on the system.
Currently, the CPU Power Policies that are used by Windows 7 and Windows Server 2008 R2 are not optimized for the dual core AMD Bulldozer module architecture. This architecture is found on AMD FX series, AMD Opteron 4200 Series, and AMD Opteron 6200 Series processors. This can result in decreased system performance with multithreaded workloads in lightly-threaded environments.
You can find out if CPU cores are parked on your system in the Windows Resource Monitor. Click on start, enter resource monitor and select the program from the search results. In the Resource Monitor, switch to the CPU tab and look at the CPU core state on the right.
This gadget will allow you to easily enable or disable core parking for your CPU. The first thing that you should do is to go to a resource manager to check if you have parked cores. The reason of doing so is that core parking is not enabled for all the multi-core CPU's.
The change will take effect without a reboot.
Now operate with cores parking available from settings in System Monitor II gadget here.
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