XNA high CPU usage with different TargetElapsedTime
With the same code i have:

5-10% CPU usage with IsFixedTimeStep=true and TargetElapsedTime = TimeSpan.FromSeconds(1 / 60f)
50-60% CPU usage with IsFixedTimeStep=true and TargetElapsedTime = TimeSpan.FromSeconds(1 / 30f)

by decreasing the frame rate one should expect less CPU usage.
I have tried with different code with similiar results.
Anyone know the cause?
XNA high CPU usage with different TargetElapsedTime
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With the same code i have:

5-10% CPU usage with IsFixedTimeStep=true and TargetElapsedTime = TimeSpan.FromSeconds(1 / 60f)
50-60% CPU usage with IsFixedTimeStep=true and TargetElapsedTime = TimeSpan.FromSeconds(1 / 30f)

by decreasing the frame rate one should expect less CPU usage.
I have tried with different code with similiar results.
Anyone know the cause?