I assumed lots of people were seeing this and it wasn't being discussed.
I see this on all my machines, that 1 core gets taken over sometimes(usage ~50% on 2-core and ~25% on 4-core).
It doesn't seem to be reliably repeatable, at least what I am seeing.
Example machine: Win 7-64bit, 8Gb RAM, corei5-2500K, KM74b4
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