The extra boost is not really something you would be using if you were doing database intensive tasks. As you're doing very little DB work - it probably will not make much of a difference at all. However you need to see if the price of upgrading to 2 x 275 is something that is cheap - and if so in the near future if you will require it. Quite often you agree to pay the extra little fee to make sure that if the system isn't performing to requirements, you can easily make it a monster with addition of another chip.
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