If the motherboard FSB is slower than the processor one, then there might be a bottle neck, I would suggest looking for a motherboard supporting the same or similar FSB speed as the processor one.
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For information on available Intel motherboards please check this link:
Thanks for your answer.
As far as I understand, the speed of the processor is 5GT/s and, if the FSB speed is only 2.5GT/s, it looks like to have a lower performance processor...