If the per-Core base frequency is 1.6GHz, then the all-Cores base frequency is also 1.6GHz. Depending upon how many Cores are active, the maximum achievable Intel Turbo Boost frequency for a particular Core will vary. The maximum frequency, 2.56GHz, can likely only be achieved when only a single Core is active (busy).
Hope this helps,
This message was posted on behalf of Intel Corporation
The information provided by N. Scott Pearson should help you a lot to understand the processor base frequency and Max Turbo frequency.
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