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This type of processors can handle configurations above the native specifications, but depends on how far you want to take it. Intel is not in position to tell what the maximum speed is when over clocking a processor. You can grab 10 CPUs of the same model with the exact same hardware configuration, over clock them and you’ll see that not all of them will be capable to reach the same speeds, precisely because they are being used out of the specifications. Intel can only grant that all of the units will run at the native maximum speed which is 4.00 GHz and Max Turbo Frequency 4.20 GHz.
You can post your question at:Overclock.net - An Overclocking Community
At that website you can get more information related to this.
NOTE: This link is being offered for your convenience and should not be viewed as an endorsement by Intel of the content, products, or services offered there.