randomizer: Could you try another comparison? I'm interested to see what's better without changing the Affinity of any of the background tasks and without killing any of them either. More like how the average person has their computer set up.

In this condition, is it better to use Set Affinity.. and manually lock Super PI to a single thread or core or is it better to leave Set Affinity... alone and allow the CPU to manage this and let it move Super PI to whatever thread it wants? What's your estimate of the average multiplier in each case? On a Core i7 with hyper threading enabled you could allow Super PI to run on the first two threads since they usually both belong to Core 0 as long as RealTemp is showing that your APIC ID as 01234567.

The new socket 1156 CPUs that have 4 or 5 bins of turbo boost available get more out of leaving C3/C6 enabled so the CPU can use the highest multiplier. The Core i7-9xx series processors that can only average an extra multiplier boost of 0.3 or 0.4 beyond the +1 turbo boost isn't really worth while. I assume that's why most performance motherboards disabled this extra boost as soon as you start overclocking. Better to have it locked at a steady 21.0 than jumping between 21.0 and 22.0 which is likely to cause instability when overclocking.