Did the experiment and obviously cores 6 and 7 (core numbering starts at 0 on my monitoring software) did less work than the others 6 cores and were 5 to 8 degrees cooler.
So only real difference between the system with all cores enabled and all but two cores enabled was in the TDP when running RealBench.
All cores x 50 186watts
6 cores x 50 2 cores at default 180watts.
Not sure what benefit there is in doing this but...
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