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Why would you want to use your internal for Time Machine?

If they're like me, they have a Mini with an internal 4200 rpm drive. So if you decide to boot to a new fast external HDD for more speed, and let the internal 4200 rpm drive do the Time Machine, you're in good shape.

At least, that's the hope. I'll know soon. I have an external 7200 rpm external drive ready to be my new boot drive when my copy of Leopard is in hand.
 
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