Quesiton about setting processor affinity for programs

I could be wrong but it seems that by default, windows sets every program to use all cores of a processor for a program by default. If this is the case... wouldn't that mean you never really get to take advantage of one core at it's full potential?

For example...

The i7-920XM is advertised at (2.26GHz ~ 3.20GHz) w/ turbo boost

You only reach that 3.20GHz if only one core is being used to it's fullest potential (with turbo boost) . But looking at windows, every program is already assigned to use all cores.

Would I have to set a program that doesn't take advantage of all cores to just use 1 or 2 cores through the "set affinity..." task in task manager to get it running at the cores it utilizes for it's fullest potential?

 

You do not have to set the processor affinities, since Windows 7 likes to run everything on as few physical cores as possible, by running tasks on virtual hyperthreaded cores before physical cores, in order to save power and avoid the performance drop which occurs when more cores are active.

This causes problems with the extreme processors, which can run all their cores at full speed, and do not benefit from several computationally intensive tasks being run on the same physical core.

Windows XP is not HT aware, so I use Core Affinity Resident in Windows XP (and also in windows 7), to automatically assign processor affinities for my DSP and FPGA software, without having to use the task manager.