Thank you for your question.
I found this document:
You'll need one of the following supported processor options in order to achieve 1333:
a. Six Core Intel(r) Xeon(r) W3680 3.33GHz, 12M L3, 6.4GT/s
b. Six Core Intel(r) Xeon(r) Processor X5670, 2.93GHz,12M L3, 6.4GT/s, turbo
c. Six Core Intel(r) Xeon(r) Processor X5650, 2.66GHz,12M L3, 6.4GT/s, turbo
Justin C Dell Technical Support | Project Sputnik
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